Polymer composition and polymer light-emitting device using same

ABSTRACT

Disclosed is a composition containing one or more aromatic ether compounds, one or more compounds having a boiling point of not less than 200° C., and one or more polymers which are charge-transporting or luminescent in a solid state. This composition is characterized in that the compounds having a boiling point of not less than 200° C. are selected from the group consisting of aliphatic compounds which may have a heteroatom, alicyclic compounds which may have a heteroatom, aromatic compounds having two or less substituents and a heterocyclic compounds having two or less substituents.

CROSS REFERENCE TO RELATED APPLICATIONS

This application is a divisional of U.S. patent application Ser. No.11/920,547, filed Nov. 16, 2007, now allowed, which is a National StageEntry of PCT/JP2006/309935, filed May 18, 2006, and claims benefit toJapanese Patent Application Nos. 2005-148204, and 2005-148205, eachfiled May 20, 2005, the contents of each of which are incorporatedherein by reference in their entirety.

TECHNICAL FIELD

The present invention relates to a polymer composition and a polymerlight-emitting device (hereinafter, sometimes referred to as a polymerLED) using the polymer composition.

BACKGROUND ART

Various light-emitting devices (polymer LEDs) comprising polymers aslight-emitting materials have been under review.

There is a method of forming the light-emitting layer of a polymer LEDby using a solution composition containing a polymer and a solvent by aninkjet method. This method is advantageous in that large-arealight-emitting devices can be fabricated at a low cost.

Known examples of such a solution composition applicable to such aninkjet method include a solution composition containing a polyfluorenederivative and a solvent (Patent Document 1); a solution compositioncontaining a poly arylene vinylene and a solvent (Patent Document 2);and a solution composition containing an aromatic ether compound and alow boiling point solvent (Patent Document 3). In addition, there isknown a device fabricated by using a mixture of 4-methyl anisole, whichis an aromatic ether compound, and 1,3,5-trimethylbenzene or1,2,3,4-tetramethylbenzene, which has three or four substituents (PatentDocument 4).

Patent Document 1: WO00/59267 pamphlet

Patent Document 2: WO02/96970 pamphlet

Patent Document 3: JP-A-2004-535653

Patent Document 4: JP-A-2003-308969

DISCLOSURE OF THE INVENTION Problems to be Solved by the Invention

By the way, there is a problem that forming a thin film with acomposition containing only a low melting point solvent or a solventhaving a high solubility of polymers provides an ununiform filmthickness. This problem is obvious on forming thin films by an inkjetmethod. Under these circumstances, there has been a desire for acomposition use of which provides a uniform film thickness on forming athin film.

Means for Solving the Problems

The present inventors have studied thoroughly in order to overcome theproblem. The inventors have, as a result, found that a film with auniform thickness is obtained by forming the film with a compositioncomprising an aromatic ether compound and a solvent having a boilingpoint equal to or higher than 200° C. and having a not so goodsolubility of polymers; or a composition comprising two or more types oforganic compounds having boiling points equal to or higher than 100° C.in which at least one type of the organic compounds are solvents havingboiling points equal to or higher than 200° C. and having a not so goodsolubility of polymers. Thus the present invention has beenaccomplished.

That is, the present invention provides

[1] A composition comprising one or more aromatic ether compounds, oneor more compounds having boiling points equal to or higher than 200° C.,and one or more polymers that transport charges or emit light in a solidstate, characterized in that the compounds having boiling points equalto or higher than 200° C. are selected from the group consisting ofaliphatic compounds that may optionally include a hetero atom, alicycliccompounds that may optionally include a hetero atom, aromatic compoundsincluding two or less substituents, and heterocyclic compounds includingtwo or less substituents; and[2] A composition comprising two or more organic compounds havingboiling points equal to or higher than 100° C. except for aromatic ethercompounds, and one or more polymers that transport charges or emit lightin a solid state, characterized in that at least one of the organiccompounds are selected from aliphatic compounds that may optionallyinclude a hetero atom and alicyclic compounds that may optionallyinclude a hetero atom, the aliphatic compounds and the alicycliccompounds having boiling points equal to or higher than 200° C.

The composition according to the present invention has an advantage thatuse of the composition provides a film with a uniform thickness onforming the film.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 shows a profile of a thin film formed with a composition 1 wherethe axis of abscissa indicates a distance (μm) of the film, and the axisof ordinate indicates a film thickness (μm) of the film;

FIG. 2 shows a profile of a thin film formed with a composition 2 wherethe axis of abscissa indicates a distance (μm) of the film, and the axisof ordinate indicates a film thickness (μm) of the film; and

FIG. 3 shows a profile of a thin film formed with a composition 6 wherethe axis of abscissa indicates a distance (μm) of the film, and the axisof ordinate indicates a film thickness (μm) of the film.

BEST MODE FOR CARRYING OUT THE INVENTION

A composition according to a first aspect of the present invention is acomposition comprising one or more types of aromatic ether compounds,one or more types of compounds having boiling points equal to or higherthan 200° C., and one or more types of polymers that transport chargesor emit light in a solid state, characterized in that the compoundshaving boiling points equal to or higher than 200° C. are selected fromthe group consisting of aliphatic compounds that may optionally includea hetero atom, alicyclic compounds that may optionally include a heteroatom, aromatic compounds including two or less substituents, andheterocyclic compounds including two or less substituents.

Examples of the aromatic ether compounds contained in the compositionaccording to the first aspect of the present invention may include:anisole, ethyl phenyl ether, propyl phenyl ether, butyl phenyl ether,methylanisole, dimethylanisole, ethylanisole, methylethylanisole,diethylanisole, propylanisole, butylanisole, pentylanisole,hexylanisole, heptylanisole, octylanisole, methyl naphthyl ether, anddiphenyl ether.

The composition according to the first aspect of the present inventioncomprises one or more types of aromatic ether compounds. The compositionpreferably comprises one or two types of aromatic ether compounds, andmore preferably one type of aromatic ether compounds for convenience inproducing the composition.

The composition according to the first aspect of the present inventioncomprises 10 to 60 wt % of the aromatic ether compounds, and morepreferably 20 to 50 wt % of the compounds based on the weight of thecomposition in view of properties of the composition such as solubilityof the polymers, viscosity, or film formability.

The compounds having boiling points equal to or higher than 200° C.contained in the composition according to the first aspect of thepresent invention are compounds having boiling points equal to or higherthan 200° C. among aliphatic compounds that may optionally include ahetero atom, alicyclic compounds that may optionally include a heteroatom, aromatic compounds including two or less substituents, orheterocyclic compounds including two or less substituents.

Examples of the aliphatic compounds that may optionally include a heteroatom may include: aliphatic hydrocarbon compounds, aliphatic alcoholcompounds, aliphatic glycol compounds, aliphatic ester compounds,aliphatic compounds containing nitrogen atoms, and aliphatic compoundscontaining sulfur atoms.

Examples of the aliphatic hydrocarbon compounds may include: n-dodecane(boiling point: 216° C.), n-tridecane (boiling point: 234° C.), andn-tetradecane (boiling point: 252 to 254° C.)

Examples of the aliphatic alcohol compounds may include: 1-nonanol(boiling point: 211° C.), n-decanol (boiling point: 231° C.), 2-decanol(boiling point: 211° C.), n-undecanol (boiling point: 241° C.),isodecanol (boiling point: 220° C.), and n-tetradecanol (boiling point:289° C.)

Examples of the aliphatic glycol compounds may include: diethyleneglycol (boiling point: 244° C.), triethylene glycol (boiling point: 287°C.), triethylene glycol dimethyl ether (boiling point: 216° C.),tetraethylene glycol dimethyl ether (boiling point: 275° C.), ethyleneglycol mono-2-ethylhexyl ether (boiling point: 229° C.), ethylene glycolmonobutyl ether (boiling point: 231° C.), ethylene glycol monohexylether (boiling point: 208° C.), ethylene glycol monobenzyl ether(boiling point: 256° C.), dipropylene glycol (boiling point: 232° C.),tripropylene glycol (boiling point: 268° C.), 1,3-butanediol (boilingpoint: 208° C.), 1,4-butanediol (boiling point: 228° C.), neopentylglycol (boiling point: 211° C.), 1,5-pentanediol (boiling point: 238 to239° C.), and 1,6-hexanediol (boiling point: 250° C.)

Examples of the aliphatic ester compounds may include: n-octyl acetate(boiling point: 208° C.) and diethyl succinate (boiling point: 218° C.)

Examples of the aliphatic compounds containing nitrogen atoms mayinclude acetamide (boiling point: 222° C.)

Examples of the aliphatic compounds containing sulfur atoms may includethiodiglycol (boiling point: 283° C.)

Examples of the alicyclic compounds that may optionally include a heteroatom may include: bicyclohexyl (boiling point: 226 to 228° C.),2-(1-cyclohexenyl)cyclohexanone (boiling point: 265° C.),λ-butyrolactone (boiling point: 203 to 204° C.), propylene carbonate(boiling point: 242° C.), δ-valerolactone (boiling point: 218 to 220°C.), isophorone (boiling point: 215° C.), N-methylpyrrolidone (boilingpoint: 202° C.), 2-pyrrolidone (boiling point: 245° C.), and sulfolane(boiling point: 287° C.)

Examples of the aromatic compounds including two or less substituentsmay include: aromatic hydrocarbon compounds, aromatic alcohol compounds,aromatic ester compounds, and aromatic carboxyl compounds.

Examples of the aromatic hydrocarbon compounds may include:n-pentylbenzene (boiling point: 205° C.), n-hexylbenzene (boiling point:226 to 227° C.), n-heptylbenzene (boiling point: 233° C.),n-octylbenzene (boiling point: 261 to 263° C.), n-nonalbenzene (boilingpoint: 282° C.), n-decylbenzene (boiling point: 293° C.),1,3-di-isopropylbenzene (boiling point: 205° C.),1,4-di-isopropylbenzene (boiling point: 205° C.), cyclohexylbenzene(boiling point: 239 to 240° C.), tetralin (boiling point: 207° C.), andbiphenyl (boiling point: 255° C.)

Examples of the aromatic alcohol compounds may include: m-cresol(boiling point: 202° C.), p-cresol (boiling point: 202° C.),p-ethylphenol (boiling point: 218 to 219° C.), 4-methoxyphenol (boilingpoint: 246° C.), o-n-propylphenol (boiling point: 214° C.),o-isopropylphenol (boiling point: 215° C.), o-s-butylphenol (boilingpoint: 226 to 228° C.), o-t-butylphenol (boiling point: 224° C.),m-t-butylphenol (boiling point: 240° C.), p-t-butylphenol (boilingpoint: 237 to 239° C.), and benzyl alcohol (boiling point: 206° C.)

Examples of the aromatic ester compounds may include ethyl benzoate(boiling point: 212° C.) and n-butyl benzoate (boiling point: 250° C.)

Examples of the aromatic carboxyl compounds may include benzoic acid(boiling point: 249° C.) and phenylacetic acid (boiling point: 266° C.)

It is preferred that the aromatic compounds including two or lesssubstituents are aromatic compounds including one or less substituentsin view of film formability.

Examples of the heterocyclic compounds including two or lesssubstituents may include quinoline (boiling point: 237° C.) andimidazole (boiling point: 257° C.)

A composition according to a first aspect of the present invention is acomposition comprising one or more types of compounds having boilingpoints equal to or higher than 200° C. selected from the groupconsisting of aliphatic compounds that may optionally include a heteroatom, alicyclic compounds that may optionally include a hetero atom,aromatic compounds including two or less substituents, and heterocycliccompounds including two or less substituents. It is preferred that thecomposition comprises one to three types of the compounds, morepreferably one or two types of the compounds, and still more preferablyone type of the compounds for convenience in producing the composition.

The compounds having boiling points equal to or higher than 200° C.contained in a composition according to a first aspect of the presentinvention are preferably selected from aliphatic compounds that mayoptionally include a hetero atom, alicyclic compounds that mayoptionally include a hetero atom, and aromatic compounds including twoor less substituents in view of film formability.

A composition according to a first aspect of the present inventionpreferably comprises 30 to 90 wt %, more preferably 40 to 80 wt % of thecompounds having boiling points equal to or higher than 200° C., basedon the weight of the composition in view of properties of thecomposition such as solubility of the polymers, viscosity, or filmformability.

A composition according to the first aspect of the present invention mayoptionally comprise a compound (hereinafter, referred to as anadditional compound) other than aromatic ether compounds and compoundshaving boiling points equal to or higher than 200° C. selected from thegroup consisting of aliphatic compounds that may optionally include ahetero atom, alicyclic compounds that may optionally include a heteroatom, aromatic compounds including two or less substituents, andheterocyclic compounds including two or less substituents. Examples ofthe additional compound may include: n-pentane, isopentane, n-hexane,isohexane, n-heptane, isoheptane, n-octane, isooctane, nonane, n-decane,n-undecane, methanol, ethanol, 1-propanol, 2-propanol, 1-butanol,2-butanol, t-butanol, 1-pentanol, 2-pentanol, 1-hexanol, 2-hexanol,1-heptanol, 2-heptanol, 1-octanol, 2-octanol, 2-nonanol, diisopropylether, dibutyl ether, ethylene glycol, ethylene glycol monoethyl ether,ethylene glycol diethyl ether, ethylene glycol monomethyl ether,ethylene glycol dimethyl ether, propylene glycol, propylene glycolmonoethyl ether, propylene glycol monomethyl ether, hexylene glycol,methyl formate, ethyl formate, n-butyl formate, n-propyl formate, methylacetate, ethyl acetate, allyl acetate, isopropyl acetate, n-butylacetate, n-propyl acetate, dimethyl succinate, diethyl oxalate, dimethyloxalate, methyl lactate, ethyl lactate, butyl lactate, methyl pyruvate,ethyl pyruvate, dimethyl malonate, diethyl malonate, dimethyl carbonate,acetaldehyde, propionaldehyde, butyraldehyde, furfural, acetone, methylethyl ketone, methyl isopropyl ketone, methyl isobutyl ketone,diisopropyl ketone, diisobutyl ketone, formic acid, acetic acid, oxalicacid, propionic acid, acetonitrile, N,N-dimethylacetamide,N,N-dimethylformamide, N,N-diisopropylethylamine, dimethyl sulfoxide,cyclopentane, cyclopentene, cyclohexane, methylcyclohexane,dimethylcyclohexane, ethylcyclohexane, cyclohexene, cycloheptane,decalin, cyclopentanol, cyclohexanol, methylcyclohexanol,dimethylcyclohexanol, cyclohexenol, cyclohexylmethanol,tetrahydrofurfuryl alcohol, furfuryl alcohol, cyclopentanone,cyclohexanone, methylcyclohexanone, dioxane, tetrahydrofuran,tetrahydropyran, benzene, toluene, o-xylene, p-xylene, m-xylene,mesitylene, 1,2,4-trimethylbenzene, tetramethylbenzene, ethylbenzene,o-diethylbenzene, m-diethylbenzene, p-diethylbenzene,1,2,4-triethylbenzene, 1,3,5-triethylbenzene, tetraethylbenzene,o-ethylmethylbenzene, p-ethylmethylbenzene, m-ethylmethylbenzene,n-propyl benzene, isopropyl benzene, n-butylbenzene, s-butylbenzene,isobutylbenzene, t-butylbenzene, phenol, o-cresol, o-ethylphenol,2,3-xylenol, 2,4-xylenol, 2,5-xylenol, 2,6-xylenol, 3,4-xylenol,3,5-xylenol, 2,4-di-t-butylphenol, 2,6-di-t-butylphenol,2-methyl-6-t-butylphenol, methyl benzoate, aniline and pyridine.

A composition of the present invention preferably comprises theadditional composition in an amount of equal to or less than 40 wt %,more preferably equal to or less than 30 wt %, still more preferablyequal to or less than 20 wt %, yet more preferably equal to or less than10 wt %, and still yet more preferably equal to or less than 1 wt %.

A composition according to the first aspect of the present invention canbe a liquid or a solid. In view of film formability, it is preferredthat the composition is in a liquid state at 50° C., more preferably ina liquid state at 40° C., and still more preferably in a liquid state at25° C. In view of storage stability, it is preferred that a solid matterdoes not precipitate at 20° C., more preferably a solid matter does notprecipitate at 10° C., and still more preferably a solid matter does notprecipitate at 0° C.

The compounds having boiling points equal to or higher than 200° C.contained in the composition according to the first aspect of thepresent invention preferably have melting points equal to or lower than25° C., more preferably equal to or lower than 20° C., and still morepreferably equal to or lower than 10° C. in view of storage stability.

A composition according to a second aspect of the present invention is acomposition comprising two or more types of organic compounds havingboiling points equal to or higher than 100° C. except for aromatic ethercompounds, and one or more types of polymers that transport charges oremit light in a solid state, characterized in that at least one type ofthe organic compounds are aliphatic compounds or alicyclic compoundshaving boiling points equal to or higher than 200° C.

The aliphatic compounds with boiling points equal to or higher than 200°C. contained in a composition according to the second aspect of thepresent invention may optionally include a hetero atom. Examples of thealiphatic compounds may include: aliphatic hydrocarbon compounds,aliphatic alcohol compounds, aliphatic glycol compounds, aliphatic estercompounds, aliphatic compounds containing nitrogen atoms, and aliphaticcompounds containing sulfur atoms. Examples of the aliphatic hydrocarboncompounds, the aliphatic alcohol compounds, the aliphatic glycolcompounds, the aliphatic ester compounds, the aliphatic compoundscontaining nitrogen atoms, and the aliphatic compounds containing sulfuratoms are described above.

It is preferred that the aliphatic compounds are aliphatic hydrocarboncompounds, aliphatic alcohol compounds, aliphatic glycol compounds, oraliphatic ester compounds, more preferably aliphatic hydrocarboncompounds or aliphatic alcohol compounds in view of film formability.

The alicyclic compounds with boiling points equal to or higher than 200°C. contained in a composition according to the second aspect of thepresent invention may optionally include a hetero atom. Examples of thealicyclic compounds may include: alicyclic hydrocarbon compounds,alicyclic ketone compounds, alicyclic lactone compounds, alicycliccarbonate compounds, alicyclic compounds containing nitrogen atoms, andalicyclic compounds containing sulfur atoms. Examples of the alicyclichydrocarbon compounds may include bicyclohexyl (boiling point: 226 to228° C.). Examples of the alicyclic ketone compounds may include2-(1-cyclohexenyl)cyclohexanone (boiling point: 265° C.) and isophorone(boiling point: 215° C.). Examples of the alicyclic lactone compoundsmay include λ-butyrolactone (boiling point: 203 to 204° C.) andδ-valerolactone (boiling point: 218 to 220° C.). Examples of thealiphatic carbonate compounds may include propylene carbonate (boilingpoint: 242° C.). Examples of the alicyclic compounds containing nitrogenatoms may include N-methylpyrrolidone (boiling point: 202° C.) and2-pyrrolidone (boiling point: 245° C.). Examples of the alicycliccompounds containing sulfur atoms may include sulfolane (boiling point:287° C.). In view of the film formability of the composition, thealicyclic compounds are preferably composed of only carbon atoms,hydrogen atoms, and oxygen atoms. More preferably, the alicycliccompounds are bicyclohexyl and 2-(1-cyclohexenyl)cyclohexanone.

A composition according to the second aspect of the present inventioncomprises one or more types of aliphatic compounds or alicycliccompounds having boiling points equal to or higher than 200° C. Thecomposition preferably comprises one to three types of the aliphaticcompounds or the alicyclic compounds, and more preferably one or twotypes of the aliphatic compounds or the alicyclic compounds forconvenience in producing the composition.

The aliphatic compounds and the alicyclic compounds having boilingpoints equal to or higher than 200° C. contained in a compositionaccording to the second aspect of the present invention preferably haveboiling points equal to or higher than 220° C. in view of forminguniform films.

A composition according to the second aspect of the present inventionpreferably comprises the aliphatic compounds or the alicyclic compoundshaving boiling points equal to or higher than 200° C. in weights equalto or greater than 30 wt %, and more preferably equal to or greater than40 wt % based on the weight of the composition in view of properties ofthe composition such as solubility of the polymers, viscosity, or filmformability.

A composition according to the second aspect of the present invention ischaracterized by comprising at least one type of an organic compoundhaving a boiling point equal to or higher than 100° C. in addition tothe aliphatic compounds or the alicyclic compounds having boiling pointsequal to or higher than 200° C.

Examples of the organic compound having boiling points equal to orhigher than 100° C. may include: aliphatic hydrocarbon compounds,aliphatic alcohol compounds, aliphatic ether compounds, aliphatic glycolcompounds, aliphatic ester compounds, aliphatic aldehyde compounds,aliphatic ketone compounds, aliphatic carboxyl compounds, aliphaticcompounds containing nitrogen atoms, aliphatic compounds containingsulfur atoms, alicyclic compounds, alicyclic compounds containing heteroatoms, aromatic hydrocarbon compounds, aromatic alcohol compounds,aromatic ester compounds, aromatic aldehyde compounds, and aromaticcarboxyl compounds.

Examples of the aliphatic hydrocarbon compounds may include: n-octane(boiling point: 126° C.), nonane (boiling point: 151° C.), n-decane(boiling point: 174° C.), and n-undecane (boiling point: 196° C.) inaddition to the aliphatic compounds having boiling points equal to orhigher than 200° C. mentioned above.

Examples of the aliphatic alcohol compounds may include: 1-butanol(boiling point: 116 to 118° C.), 1-pentanol (boiling point: 136 to 138°C.), 2-pentanol (boiling point: 118 to 119° C.), 1-hexanol (boilingpoint: 157° C.), 2-hexanol (boiling point: 136° C.), 1-heptanol (boilingpoint: 176° C.), 2-heptanol (boiling point: 160 to 162° C.), 1-octanol(boiling point: 196° C.), 2-octanol (boiling point: 174 to 181° C.), and2-nonanol (boiling point: 193 to 194° C.) in addition to the aliphaticcompounds having boiling points equal to or higher than 200° C.mentioned above.

Examples of the aliphatic ether compounds may include dibutyl ether(boiling point: 137 to 143° C.)

Examples of the aliphatic glycol compounds may include: ethylene glycol(boiling point: 197° C.), ethylene glycol monoethyl ether (boilingpoint: 135° C.), ethylene glycol diethyl ether (boiling point: 124° C.),ethylene glycol monomethyl ether (boiling point: 124° C.), propyleneglycol (boiling point: 187° C.), propylene glycol monoethyl ether,propylene glycol monomethyl ether (boiling point: 119 to 122° C.), andhexylene glycol (boiling point: 198° C.) in addition to the aliphaticcompounds having boiling points equal to or higher than 200° C.mentioned above.

Examples of the aliphatic ester compounds may include: n-butyl formate(boiling point: 107° C.), allyl acetate (boiling point: 103 to 104° C.),n-butyl acetate (boiling point: 120 to 125° C.), dimethyl succinate(boiling point: 195° C.), diethyl oxalate (boiling point: 185° C.),dimethyl oxalate (boiling point: 134 to 137° C.), methyl lactate(boiling point: 145° C.), ethyl lactate (boiling point: 154° C.), methylpyruvate (boiling point: 165° C.), ethyl pyruvate (boiling point: 156°C.), dimethyl malonate (boiling point: 181° C.), and diethyl malonate(boiling point: 198 to 199° C.) in addition to the aliphatic compoundshaving boiling points equal to or higher than 200° C. mentioned above.

Examples of the aliphatic aldehyde compounds may include furfural(boiling point: 161° C.)

Examples of the aliphatic ketone compounds may include: methyl isobutylketone (boiling point: 118° C.), diisopropyl ketone (boiling point: 124°C.), and diisobutyl ketone (boiling point: 163 to 173° C.)

Examples of the aliphatic carboxyl compounds may include: formic acid(boiling point: 101° C.), acetic acid (boiling point: 117 to 118° C.),and propionic acid (boiling point: 141° C.)

Examples of the aliphatic compounds containing nitrogen atoms mayinclude: N,N-dimethylacetamide (boiling point: 165 to 166° C.),N,N-dimethylformamide (boiling point: 153° C.), andN,N-diisopropylethylamine (boiling point: 127° C.) in addition to thealiphatic compounds having boiling points equal to or higher than 200°C. mentioned above.

Examples of the aliphatic compounds containing sulfur atoms may includedimethyl sulfoxide (boiling point: 189° C.) in addition to the aliphaticcompounds having boiling points equal to or higher than 200° C.mentioned above.

Examples of the alicyclic compounds may include: methylcyclohexane(boiling point: 101° C.), dimethylcyclohexane (boiling point: 120 to129° C.), ethylcyclohexane (boiling point: 132° C.), cycloheptane(boiling point: 116 to 118° C.), and decalin (boiling point: 187 to 195°C.) in addition to the alicyclic compounds having boiling points equalto or higher than 200° C. mentioned above.

Examples of the alicyclic compounds containing hetero atoms may include:cyclopentanol (boiling point: 139 to 140° C.), cyclohexanol (boilingpoint: 160 to 161° C.), methylcyclohexanol (boiling point: 171 to 173°C.), dimethylcyclohexanol (boiling point: 186° C.), cyclohexenol(boiling point: 164 to 166° C.), cyclohexylmethanol (boiling point: 181°C.), tetrahydrofurfuryl alcohol (boiling point: 178° C.), furfurylalcohol (boiling point: 170 to 171° C.), cyclopentanone (boiling point:130 to 131° C.), cyclohexanone (boiling point: 155° C.), dioxane(boiling point: 102° C.), and methylcyclohexanone (boiling point: 162 to171° C.) in addition to the alicyclic compounds having boiling pointsequal to or higher than 200° C. mentioned above. Preferred alicycliccompounds containing hetero atoms are cyclopentanol, cyclohexanol,methylcyclohexanol, dimethylcyclohexanol, cyclopentanone, andcyclohexanone in view of the properties of the composition such as filmformability.

Examples of the aromatic hydrocarbon compounds may include: toluene(boiling point: 111° C.), o-xylene (boiling point: 143 to 145° C.),p-xylene (boiling point: 138° C.), m-xylene (boiling point: 138 to 139°C.), mesitylene (162 to 164° C.), 1,2,4-trimethylbenzene (boiling point:168° C.), ethylbenzene (boiling point: 136° C.), o-diethylbenzene(boiling point: 183 to 184° C.), m-diethylbenzene (boiling point: 181°C.), p-diethylbenzene (boiling point: 184° C.), o-ethylmethylbenzene(boiling point: 164 to 165° C.), p-ethylmethylbenzene (boiling point:162° C.), m-ethylmethylbenzene (boiling point: 161° C.), n-propylbenzene (boiling point: 159° C.), isopropyl benzene (boiling point: 153°C.), n-butylbenzene (boiling point: 183° C.), s-butylbenzene (boilingpoint: 173° C.), isobutylbenzene (boiling point: 173° C.),t-butylbenzene (boiling point: 169° C.), n-pentylbenzene (boiling point:205° C.), n-hexylbenzene (boiling point: 226 to 227° C.),n-heptylbenzene (boiling point: 233° C.), n-octylbenzene (boiling point:261 to 263° C.), n-nonalbenzene (boiling point: 282° C.), n-decylbenzene(boiling point: 293° C.), 1,3-di-isopropylbenzene (boiling point: 205°C.), 1,4-di-isopropylbenzene (boiling point: 205° C.), cyclohexylbenzene(boiling point: 239 to 240° C.), tetralin (boiling point: 207° C.), andbiphenyl (boiling point: 255° C.)

Examples of the aromatic alcohol compounds may include: phenol (boilingpoint: 182° C.), o-cresol (boiling point: 190 to 195° C.), o-ethylphenol(boiling point: 195 to 197° C.), m-cresol (boiling point: 202° C.),p-cresol (boiling point: 202° C.), p-ethylphenol (boiling point: 218 to219° C.), 4-methoxyphenol (boiling point: 246° C.), o-n-propylphenol(boiling point: 214° C.), o-isopropylphenol (boiling point: 215° C.),o-s-butylphenol (boiling point: 226 to 228° C.), o-t-butylphenol(boiling point: 224° C.), m-t-butylphenol (boiling point: 240° C.),p-t-butylphenol (boiling point: 237 to 239° C.), and benzyl alcohol(boiling point: 206° C.)

Examples of the aromatic ester compounds may include: methyl benzoate(boiling point: 199° C.), ethyl benzoate (boiling point: 212° C.), andn-butyl benzoate (boiling point: 250° C.)

Examples of the aromatic aldehyde compounds may include benzaldehyde(boiling point: 178° C.)

Examples of the aromatic carboxyl compounds may include benzoic acid(boiling point: 249° C.) and phenylacetic acid (boiling point: 266° C.)

In view of the properties of the composition such as film formability,preferred organic compounds having boiling points equal to or higherthan 100° C. are aliphatic hydrocarbon compounds, aliphatic alcoholcompounds, aliphatic ester compounds, aliphatic ketone compounds,alicyclic compounds, alicyclic compounds containing hetero atoms,aromatic hydrocarbon compounds, aromatic alcohol compounds, and aromaticester compounds.

A composition according to the second aspect of the present inventioncomprising an aromatic compound except for aromatic ether compoundspreferably has a boiling point equal to or lower than 250° C., and morepreferably equal to or lower than 220° C. in view of forming uniformfilms. The aromatic compound preferably has a lower boiling point thanaliphatic compounds or alicyclic compounds having boiling points equalto or higher than 200° C. contained in the composition.

A composition according to the second aspect of the present invention ischaracterized by comprising two or more types of organic compoundshaving boiling points equal to or higher than 100° C. In view ofviscosity, the organic compounds preferably have boiling points equal toor higher than 120° C., more preferably equal to or higher than 150° C.,and still more preferably equal to or higher than 170° C.

A composition according to the second aspect of the present inventionmay optionally comprise a compound except for aromatic ether compoundsin addition to the organic compounds having boiling points equal to orhigher than 100° C. Examples of such a compound may include compoundshaving boiling points lower than 100° C. The composition preferablycontains the compound in an amount equal to or less than 20 wt %, morepreferably equal to or less than 10 wt %, and still more preferablyequal to or less than 1 wt % based on the weight of the composition ofthe present invention.

A composition according to the second aspect of the present inventioncan be a liquid or a solid. In view of film formability, it is preferredthat the composition is in a liquid state at 50° C., more preferably ina liquid state at 40° C., and still more preferably in a liquid state at25° C. In view of storage stability, it is preferred that a solid matterdoes not precipitate at 20° C., more preferably a solid matter does notprecipitate at 10° C., and still more preferably a solid matter does notprecipitate at 0° C.

The aliphatic compounds and the alicyclic compounds having boilingpoints equal to or higher than 200° C. contained in the compositionaccording to the second aspect of the present invention preferably havemelting points equal to or lower than 25° C., more preferably equal toor lower than 20° C., and still more preferably equal to or lower than10° C. in view of storage stability.

The polymers contained in compositions according to the presentinvention preferably have number average molecular weights of 1.0×10³ to1.0×10⁷, more preferably 5.0×10³ to 1.0×10⁶, and still more preferably1.0×10⁴ to 2.0×10⁵ in view of properties of the compositions such assolubility, viscosity, and film formability.

The polymers contained in the compositions according to the presentinvention preferably have weight average molecular weights of 1.0×10³ to1.0×10⁷, more preferably 1.0×10⁴ to 2.0×10⁶, and still more preferably5.0×10⁴ to 1.0×10⁶ in view of properties of the compositions such assolubility, viscosity, and film formability.

The compositions according to the present invention preferably comprises0.1 to 5 wt % of the polymers, more preferably 0.5 to 2 wt % based onthe weight of the compositions in view of properties of the compositionssuch as solubility, viscosity, and a cost for forming films.

A composition according to the present invention preferably has aviscosity of 1 to 20 mPa·s, and more preferably 3 to 15 mPa·s at 25° C.in view of properties of the composition such as film formability.

The polymers contained in the compositions according to the presentinvention are not particularly restricted as long as the polymerstransport charges or emit light in a solid state. The charge transportpolymers are polymers that transport negative charges (electrons) orpositive charges (holes), and the polymers may transport both electronsand holes. Charge transport can be tested by a technique of determiningcharge transport by using cyclic voltammetry, a technique of fabricatinga device and testing charge transport there or various techniques knownin the art. Electrons and holes can recombine in the polymers thattransport charges to emit electroluminescence. Examples of the polymersthat emit light in a solid state may include polymers that emitfluorescence in a solid state and polymers that emit phosphorescence ina solid state. The polymers that emit light in a solid state maytransport charges or emit electroluminescence.

Thin films formed with the compositions according to the presentinvention are applicable to various uses such as polymerelectroluminescence, organic transistors, polymer capacitors, secondarybatteries, solar cells, sensors, thermoelectric transducers, capacitors,actuators, antistatic agents, gas separation membranes, electromagneticshielding, lasers, electrophotographic photosensitive materials, ororganic super conductors. Polymers contained in the compositions areselected appropriately according to the uses of the compositions.

As for the use for polymer LEDs, light-emitting layers, electrontransport layers, and hole transport layers can be formed withcompositions according to the present invention.

When light-emitting layers are formed with compositions according to thepresent invention, the polymers contained in the compositions preferablyinclude at least one repeating unit among arylene groups, divalentheterocyclic groups, divalent groups having metal complex structures,and divalent aromatic amines.

The polymers with the repeating unit(s) may further comprise structuresrepresented by —CR_(a1)═CR_(a2)—, —C≡C—, —N(R_(a3))—, or—(SiR_(a4)R_(a5))_(b)— without impairing the light-emitting property.R_(a1) and R_(a2) independently represent a hydrogen atom, an alkylgroup, an aryl group, a monovalent heterocyclic group, a carboxyl group,a substituted carboxyl group, or a cyano group. R_(a3), R_(a4), andR_(a5) independently represent a group including a hydrogen atom, analkyl group, an aryl group, a monovalent heterocyclic group, anarylalkyl group, or a substituted amino group. b represents an integerof 1 to 12. When any of R_(a1), R_(a2), R_(a3), R_(a4), and R_(a5) aretwo or more, these Rs may be the same or different.

The arylene group used herein refers to an atom group obtained byremoving two hydrogen atoms from an aromatic hydrocarbon and includes anarylene group having a condensed ring, and an aryl group having two ormore independent benzene rings or condensed rings directly joinedthereto or joined via a group such as vinylene. The arylene group mayhave a substituent. The type of substituent is not particularly limited.In view of solubility, fluorescent properties, ease of synthesis andcharacteristics of the resultant device, preferable examples of thesubstituent include an alkyl group, alkoxy group, alkylthio group, arylgroup, aryloxy group, arylthio group, arylalkyl group, arylalkoxy group,arylalkylthio group, arylalkenyl group, arylalkynyl group, amino group,substituted amino group, silyl group, substituted silyl group, halogenatom, acyl group, acyloxy group, imine residue, amide group, acid imidogroup, monovalent heterocyclic group, carboxyl group, substitutedcarboxyl group and cyano group.

The number of carbon atoms of the arylene group except a substituent isgenerally about 6 to 60, and preferably 6 to 20. The total number ofcarbon atoms of the arylene group including that of a substituent isgenerally about 6 to 100.

Examples of the arylene group include a phenylene group (for example,the following formulas 1 to 3), naphthalene-diyl group (the followingformulas 4 to 13), anthracene-diyl group (the following formulas 14 to19), biphenyl-diyl group (the following formulas 20 to 25),fluorene-diyl group (the following formulas 36 to 38), terphenyl-diylgroup (the following formulas 26 to 28), condensed ring compound group(the following formulas 29 to 35), stilbene-diyl (the following formulasA to D), distilbene-diyl (the following formulas E and F) andindenonaphthalene-diyl (the following formulas G to N).

The divalent heterocyclic group refers to the remaining atom groupobtained by removing two hydrogen atoms from a heterocyclic compound andmay have a substituent.

The heterocyclic compound refers to an organic compound having a ringstructure which may not be necessarily constituted of carbon atoms aloneand may include a hetero atom such as oxygen, sulfur, nitrogen,phosphorus, boron or arsenic. Of the divalent heterocyclic groups, anaromatic heterocyclic group is preferable. The type of substituent isnot particularly limited; however, in view of solubility, fluorescentproperties, ease of synthesis and characteristics of the resultantdevice, preferable examples of the substituent include an alkyl group,alkoxy group, alkylthio group, aryl group, aryloxy group, arylthiogroup, arylalkyl group, arylalkoxy group, arylalkylthio group,arylalkenyl group, arylalkynyl group, amino group, substituted aminogroup, silyl group, substituted silyl group, halogen atom, acyl group,acyloxy group, imine residue, amide group, acid imido group, monovalentheterocyclic group, carboxyl group, substituted carboxyl group and cyanogroup.

The number of carbon atoms of the divalent heterocyclic group exceptthat of a substituent is generally about 3 to 60. The total number ofcarbon atoms of the divalent heterocyclic group including that of asubstituent is generally about 3 to 100.

Examples of the divalent heterocyclic group include

divalent pyridine-diyl groups (the following formulas 39 to 44),

diazaphenylene groups (the following formulas 45 to 48),

quinolinediyl groups (the following formulas 49 to 63),

quinoxalinediyl groups (the following formulas 64 to 68),

acridinediyl groups (the following formulas 69 to 72),

bipyridyldiyl groups (the following formulas 73 to 75), andphenanthrolinediyl groups (the following formulas 76 to 78) containingnitrogen as a hetero atom;

groups having a fluorene structure and containing oxygen, silicon,nitrogen, selenium or sulfur, etc., as a hetero atom (the followingformulas 79 to 93);

5-membered heterocyclic groups containing oxygen, silicon, nitrogen,sulfur, selenium, boron or phosphorus, etc., as a hetero atom (thefollowing formulas 94 to 98, O to Z, and AA to AC);

5-membered condensed heterocyclic groups containing oxygen, silicon,nitrogen, sulfur, selenium or sulfur, etc., as a hetero atom (thefollowing formulas 99 to 110);

dimmers or oligomers formed of 5-membered heterocyclic groups containingoxygen, silicon, nitrogen, sulfur or selenium, etc., as a hetero atomand joined at the α-position of the hetero atom the following formulas111 and 112);

5-membered heterocyclic groups containing oxygen, silicon, nitrogen,sulfur or selenium, etc., as a hetero atom and joined to a phenyl groupat the α-position of the hetero atom (the following formulas 113 to119);

5-membered condensed heterocyclic groups containing oxygen, nitrogen orsulfur, etc., as a hetero atom and substituted with a phenyl group,furyl group, thienyl group (the following formulas 120 to 125); and

6-membered heterocyclic groups (the following formulas AD to AG)containing oxygen and nitrogen as hetero atoms.

The divalent group having a metal complex structure refers to a divalentgroup obtained by removing two hydrogen atoms from an organic ligand ofa metal complex having the organic ligand.

The number of carbon atoms of the organic ligand is generally about 4 to60. Examples thereof include 8-quinolinol and a derivative thereof,benzoquinolinol and a derivative thereof, 2-phenyl-pyridine and aderivative thereof, 2 phenyl-benzothiazole and a derivative thereof, 2phenyl-benzoxazole and a derivative thereof, and porphyrin and aderivative thereof.

Examples of the core metal of the complex include aluminum, zinc,beryllium, iridium, platinum, gold, europium and terbium.

Examples of the metal complex having an organic ligand include metalcomplexes known as a low-molecular weight fluorescent material andphosphorescent material and triplet light-emitting complexes.

Specific examples of the divalent group having a metal complex structureinclude those represented by the following formulas 126 to 132.

In the formulas 1 to 132, A to Z, and AA to AZ, Rs each independentlyrepresent a hydrogen atom, an alkyl group, alkoxy group, alkylthiogroup, aryl group, aryloxy group, arylthio group, arylalkyl group,arylalkoxy group, arylalkylthio group, arylalkenyl group, arylalkynylgroup, amino group, substituted amino group, silyl group, substitutedsilyl group, halogen atom, acyl group, acyloxy group, imine residue,amide group, acid imido group, monovalent heterocyclic group, carboxylgroup, substituted carboxyl group, nitro group, or cyano group.

The carbon atoms included in the groups of the formulas 1 to 132 may besubstituted with nitrogen atoms, oxygen atoms, or sulfur atoms. Thehydrogen atoms included in the groups of the formulas 1 to 132 may besubstituted with fluorine atoms. Neighboring Rs in the formulas 1 to 132may be linked to form a ring.

The alkyl group may be linear, branched or cyclic, and the number ofcarbon atoms is generally about 1 to 20, preferably 3 to 20. Specificexamples thereof include a methyl group, ethyl group, propyl group,isopropyl group, n-butyl group, isobutyl group, t-butyl group, pentylgroup, isoamyl group, hexyl group, cyclohexyl group, heptyl group, octylgroup, 2-ethylhexyl group, nonyl group, decyl group, 3,7-dimethyloctylgroup, lauryl group, trifluoromethyl group, pentafluoroethyl group,perfluorobutyl group, perfluorohexyl group and perfluorooctyl group.Preferred alkyl groups are a pentyl group, isoamyl group, hexyl group,octyl group, 2-ethylhexyl group, decyl group, and 3,7-dimethyloctylgroup to balance viewpoints such as solubility in organic solvents,device characteristics, and ease of synthesis, and heat resistance.

The alkoxy group may be linear, branched or cyclic and the number ofcarbon atoms is generally about 1 to 20, preferably 3 to 20. Specificexamples thereof include a methoxy group, ethoxy group, propyloxy group,isopropyloxy group, butoxy group, isobutoxy group, t-butoxy group,pentyloxy group, hexyloxy group, cyclohexyloxy group, heptyloxy group,octyloxy group, 2-ethylhexyloxy group, nonyloxy group, decyloxy group,3,7-dimethyloctyloxy group, lauryloxy group, trifluoromethoxy group,pentafluoroethoxy group, perfluorobutoxy group, perfluorohexyl group,perfluorooctyl group, methoxymethyloxy group, and 2-methoxyethyloxygroup. Preferred alkoxy groups are a pentyloxy group, hexyloxy group,octyloxy group, 2-ethylhexyloxy group, decyloxy group, and3,7-dimethyloctyloxy group to balance viewpoints such as solubility inorganic solvents, device characteristics, and ease of synthesis, andheat resistance.

The alkylthio group may be linear, branched or cyclic and the number ofcarbon atoms is generally about 1 to 20, preferably 3 to 20. Specificexamples thereof include a methylthio group, ethylthio group, propylthiogroup, isopropylthio group, butylthio group, isobutylthio group,t-butylthio group, pentylthio group, hexylthio group, cyclohexylthiogroup, heptylthio group, octylthio group, 2-ethylhexylthio group,nonylthio group, decylthio group, 3,7-dimethyloctylthio group,laurylthio group and trifluoromethylthio group. Preferred alkylthiogroups are a pentylthio group, hexylthio group, octylthio group,2-ethylhexylthio group, decylthio group, and 3,7-dimethyloctylthio groupto balance viewpoints such as solubility in organic solvents, devicecharacteristics, and ease of synthesis, and heat resistance.

The aryl group is the remaining atom group obtained by removing a singlehydrogen atom from an aromatic hydrocarbon and includes an aryl grouphaving a condensed ring and an aryl group having two or more independentbenzene rings or condensed rings directly joined thereto or joined via agroup such as vinylene. The aryl group generally has about 6 to 60carbon atoms, and preferably, 7 to 48 carbon atoms. Specific examplesthereof include a phenyl group, C₁-C₁₂ alkoxyphenyl group (C₁-C₁₂represents that the number of carbon atoms is 1 to 12 and hereinafter,the same definition will be also applied), C₁-C₁₂ alkylphenyl group,1-naphthyl group, 2-naphthyl group, 1-anthracenyl group, 2-anthracenylgroup, 9-anthracenyl group and pentafluorophenyl group, and a C₁-C₁₂alkoxyphenyl group and C₁-C₁₂ alkylphenyl group are preferable in viewof solubility in organic solvents, device characteristics, and ease ofsynthesis, and so on. Specific examples of the C₁-C₁₂ alkoxy includemethoxy, ethoxy, propyloxy, i-propyloxy, butoxy, i-butoxy, t-butoxy,pentyloxy, hexyloxy, cyclohexyloxy, heptyloxy, octyloxy,2-ethylhexyloxy, nonyloxy, decyloxy, 3,7-dimethyloctyloxy and lauryloxy.

Specific examples of the C₁-C₁₂ alkylphenyl group include a methylphenylgroup, ethylphenyl group, dimethylphenyl group, propylphenyl group,mesityl group, methylethylphenyl group, i-propylphenyl group,butylphenyl group, i-butylphenyl group, t-butylphenyl group,pentylphenyl group, isoamylphenyl group, hexylphenyl group, heptylphenylgroup, octylphenyl group, nonylphenyl group, decylphenyl group anddodecylphenyl group.

The aryloxy group generally has about 6 to 60 carbon atoms andpreferably 7 to 48. Specific examples thereof include a phenoxy group,C₁-C₁₂ alkoxyphenoxy group, C₁-C₁₂ alkylphenoxy group, 1-naphthyloxygroup, 2-naphthyloxy group and pentafluorophenyloxy group, and a C₁-C₁₂alkoxyphenoxy group and C₁-C₁₂ alkylphenoxy group are preferable in viewof solubility in organic solvents, device characteristics, and ease ofsynthesis, and so on.

Specific examples of the C₁-C₁₂ alkoxy include methoxy, ethoxy,propyloxy, isopropyloxy, butoxy, isobutoxy, t-butoxy, pentyloxy,hexyloxy, cyclohexyloxy, heptyloxy, octyloxy, 2-ethylhexyloxy, nonyloxy,decyloxy, 3,7-dimethyloctyloxy and lauryloxy.

Specific examples of the C₁-C₁₂ alkylphenoxy group include amethylphenoxy group, ethylphenoxy group, dimethylphenoxy group,propylphenoxy group, 1,3,5-trimethylphenoxy group, methylethylphenoxygroup, isopropylphenoxy group, butylphenoxy group, isobutylphenoxygroup, t-butylphenoxy group, pentylphenoxy group, isoamylphenoxy group,hexylphenoxy group, heptylphenoxy group, octylphenoxy group,nonylphenoxy group, decylphenoxy group and dodecylphenoxy group.

The arylthio group generally has about 3 to 60 carbon atoms. Specificexamples thereof include a phenylthio group, C₁-C₁₂ alkoxyphenylthiogroup, C₁-C₁₂ alkylphenylthio group, 1-naphthylthio group,2-naphthylthio group, and pentafluorophenylthio group. Preferredarylthio groups are a C₁-C₁₂ alkoxyphenylthio group and C₁-C₁₂alkylphenylthio group in view of solubility in organic solvents, devicecharacteristics, and ease of synthesis, and so on.

The arylalkyl group generally has about 7 to 60 carbon atoms andpreferably 7 to 48. Specific examples thereof include a phenyl-C₁-C₁₂alkyl group, C₁-C₁₂ alkoxyphenyl-C₁-C₁₂ alkyl group, C₁-C₁₂alkylphenyl-C₁-C₁₂ alkyl group, 1-naphthyl-C₁-C₁₂ alkyl group and2-naphthyl-C₁-C₁₂ alkyl group. Preferred arylalkyl groups are a C₁-C₁₂alkoxyphenyl-C₁-C₁₂ alkyl group and C₁-C₁₂ alkylphenyl-C₁-C₁₂ alkylgroup in view of solubility in organic solvents, device characteristics,and ease of synthesis, and so on.

The arylalkoxy group generally has about 7 to 60 carbon atoms andpreferably 7 to 48. Specific examples thereof include a phenyl-C₁-C₁₂alkoxy group such as a phenylmethoxy group, phenylethoxy group,phenylbutoxy group, phenylpentyloxy group, phenylhexyloxy group,phenylheptyloxy group, or phenyloctyloxy group; C₁-C₁₂alkoxyphenyl-C₁-C₁₂ alkoxy group; C₁-C₁₂ alkylphenyl-C₁-C₁₂ alkoxygroup; 1-naphthyl-C₁-C₁₂ alkoxy group; and 2-naphthyl-C₁-C₁₂ alkoxygroup. Preferred arylalkoxy groups are a C₁-C₁₂ alkoxyphenyl-C₁-C₁₂alkoxy group and C₁-C₁₂ alkylphenyl-C₁-C₁₂ alkoxy group in view ofsolubility in organic solvents, device characteristics, and ease ofsynthesis, and so on.

The arylalkylthio group generally has about 7 to 60 carbon atoms andpreferably 7 to 48. Specific examples thereof include a phenyl-C₁-C₁₂alkylthio group, C₁-C₁₂ alkoxyphenyl-C₁-C₁₂ alkylthio group, C₁-C₁₂alkylphenyl-C₁-C₁₂ alkylthio group, 1-naphthyl-C₁-C₁₂ alkylthio groupand 2-naphthyl-C₁-C₁₂ alkylthio group. Preferred arylalkylthio groupsare a C₁-C₁₂ alkoxyphenyl-C₁-C₁₂ alkylthio group and C₁-C₁₂alkylphenyl-C₁-C₁₂ alkylthio group in view of solubility in organicsolvents, device characteristics, and ease of synthesis, and so on.

The arylalkenyl group generally has about 8 to 60 carbon atoms. Specificexamples thereof include a phenyl-C₂-C₁₂ alkenyl group, C₁-C₁₂alkoxyphenyl-C₂-C₁₂ alkenyl group, C₁-C₁₂ alkylphenyl-C₂-C₁₂ alkenylgroup, 1-naphthyl-C₂-C₁₂ alkenyl group and 2-naphthyl-C₂-C₁₂ alkenylgroup; and a C₁-C₁₂ alkoxyphenyl-C₂-C₁₂ alkenyl group and C₂-C₁₂alkylphenyl-C₁-C₁₂ alkenyl group are preferable in view of solubility inorganic solvents, device characteristics, and ease of synthesis, and soon.

The arylalkynyl group generally has about 8 to 60 carbon atoms. Specificexamples thereof include a phenyl-C₂-C₁₂ alkynyl group, C₁-C₁₂alkoxyphenyl-C₂-C₁₂ alkynyl group, C₁-C₁₂ alkylphenyl-C₂-C₁₂ alkynylgroup, 1-naphthyl-C₂-C₁₂ alkynyl group and 2-naphthyl-C₂-C₁₂ alkynylgroup; and a C₁-C₁₂ alkoxyphenyl-C₂-C₁₂ alkynyl group and C₁-C₁₂alkylphenyl-C₂-C₁₂ alkynyl group are preferable in view of solubility inorganic solvents, device characteristics, and ease of synthesis, and soon.

The substituted amino group may include amino groups substituted with asingle group or two groups selected from the group consisting of analkyl group, aryl group, arylalkyl group and a monovalent heterocyclicgroup. The alkyl group, aryl group, arylalkyl group or a monovalentheterocyclic group may have a substituent. The number of carbon atoms ofthe substituted amino group excluding that of the substituent isgenerally about 1 to 60, and preferably, 2 to 48.

Specific examples include a methylamino group, dimethylamino group,ethylamino group, diethylamino group, propylamino group, dipropylaminogroup, isopropylamino group, diisopropylamino group, butylamino group,isobutylamino group, t-butylamino group, pentylamino group, hexylaminogroup, cyclohexylamino group, heptylamino group, octylamino group,2-ethylhexylamino group, nonylamino group, decylamino group,3,7-dimethyloctylamino group, laurylamino group, cyclopentylamino group,dicyclopentylamino group, cyclohexylamino group, dicyclohexylaminogroup, pyrrolidyl group, piperidyl group, ditrifluoromethylamino group,phenylamino group, diphenylamino group, C₁-C₁₂alkoxyphenylamino group,di(C₁-C₁₂alkoxyphenyl)amino group, di(C₁-C₁₂alkylphenyl)amino group,1-naphthylamino group, 2-naphthylamino group, pentafluorophenylaminogroup, pyridylamino group, pyridazinylamino group, pyrimidylamino group,pyrazylamino group, triazylamino group phenyl-C₁-C₁₂alkylamino group,C₁-C₁₂alkoxyphenyl-C₁-C₁₂alkylamino group,C₁-C₁₂alkylphenyl-C₁-C₁₂alkylamino group,di(C₁-C₁₂alkoxyphenyl-C₁-C₁₂alkyl) amino group,di(C₁-C₁₂alkylphenyl-C₁-C₁₂alkyl) amino group,1-naphthyl-C₁-C₁₂alkylamino group and 2-naphthyl-C₁-C₁₂alkylamino group.

The substituted silyl group may include silyl groups substituted with 1,2 or 3 groups selected from the group consisting of an alkyl group, arylgroup, arylalkyl group and a monovalent heterocyclic group. Thesubstituted silyl group generally has about 1 to 60 carbon atoms, andpreferably 3 to 48 carbon atoms. Note that the alkyl group, aryl group,arylalkyl group and a monovalent heterocyclic group may have asubstituent.

Specific examples thereof include a trimethylsilyl group, triethylsilylgroup, tripropylsilyl group, triisopropylsilyl group,dimethyl-isopropylsilyl group, diethyl-isopropylsilyl group,t-butylsilyldimethylsilyl group, pentyldimethylsilyl group,hexyldimethylsilyl group, heptyldimethylsilyl group, octyldimethylsilylgroup, 2-ethylhexyl-dimethylsilyl group, nonyldimethylsilyl group,decyldimethylsilyl group, 3,7-dimethyloctyl-dimethylsilyl group,lauryldimethylsilyl group, phenyl-C₁-C₁₂alkylsilyl group,C₁-C₁₂alkoxyphenyl-C₁-C₁₂alkylsilyl group,C₁-C₁₂alkylphenyl-C₁-C₁₂alkylsilyl group, 1-naphthyl-C₁-C₁₂alkylsilylgroup, 2-naphthyl-C₁-C₁₂alkylsilyl group,phenyl-C₁-C₁₂alkyldimethylsilyl group, triphenylsilyl group,tri-p-xylylsilyl group, tribenzylsilyl group, diphenylmethylsilyl group,t-butyldiphenylsilyl group and dimethylphenylsilyl group.

Examples of the halogen atom include a fluorine atom, chlorine atom,bromine atom and iodine atom.

The acyl group generally has about 2 to 20 carbon atoms, and preferably,2 to 18 carbon atoms. Specific examples thereof include an acetyl group,propionyl group, butyryl group, isobutyryl group, pivaloyl group,benzoyl group, trifluoroacetyl group and pentafluorobenzoyl group.

The acyloxy group generally has about 2 to 20 carbon atoms, andpreferably, 2 to 18 carbon atoms. Specific examples thereof include anacetoxy group, propionyloxy group, butyryloxy group, isobutyryloxygroup, pivaloyloxy group, benzoyloxy group, trifluoroacetyloxy group andpentafluorobenzoyloxy group.

The imine residue refers to a residue obtained by removing a singlehydrogen atom from an imine compound. The imine compound is an organiccompound including —N═C— intramolecularly. Examples of the iminecompound may include aldimine, ketimine, and compounds in which thehydrogen atom on the N atom of aldimine or ketimine is substituted withan alkyl group or the like. The imine residue generally has about 2 to20 carbon atoms, and preferably 2 to 18 carbon atoms. Specific examplesthereof include groups represented by the following structural formulas.

The amide group has about 2 to 20 carbon atoms, and preferably, 2 to 18carbon atoms. Specific examples thereof include a formamide group,acetamido group, propioamide group, butyroamide group, benzamido group,trifluoroacetamido group, pentafluorobenzamide group, diformamide group,diacetamide group, dipropyoamide group, dibutyroamide group, dibenzamidegroup, ditrifluoroacetamide group and dipentaflurobenzamide group.

The acid imido group may be a residue obtained by removing a hydrogenatom bound to the nitrogen atom of the acid imido and has about 4 to 20carbon atoms. Specific examples thereof include groups representedbelow.

The monovalent heterocyclic group refers to an atom group obtained byremoving a single hydrogen atom from a heterocyclic compound andgenerally has about 4 to 60 carbon atoms, and preferably, 4 to 20 carbonatoms. Note that the number of carbon atoms of the heterocyclic groupdoes not include the number of carbon atoms of a substituent. Theheterocyclic compound herein refers to an organic compound having a ringstructure which may not be necessarily constituted of carbon atoms aloneand may include a hetero atom such as oxygen, sulfur, nitrogen,phosphorus, boron, or silicon. Specific examples of the monovalentheterocyclic group include a thienyl group, C₁-C₁₂ alkylthienyl group,pyrrolyl group, furyl group, pyridyl group, C₁-C₁₂ alkylpyridyl group,piperidyl group, quinolyl group and isoquinolyl group; and a thienylgroup, C₁-C₁₂ alkylthienyl group, pyridyl group and C₁-C₁₂ alkylpyridylgroup are preferable.

The substituted carboxyl group may include a carboxyl group substitutedwith an alkyl group, aryl group, arylalkyl group or monovalentheterocyclic group and generally has about 2 to 60 carbon atoms, andpreferably, 2 to 48 carbon atoms. Specific examples thereof include amethoxycarbonyl group, ethoxycarbonyl group, propoxycarbonyl group,isopropoxycarbonyl group, butoxycarbonyl group, isobutoxycarbonyl group,t-butoxycarbonyl group, pentyloxycarbonyl group, hexyloxycarbonyl group,cyclohexyloxycarbonyl group, heptyloxycarbonyl group, octyloxycarbonylgroup, 2-ethylhexyloxycarbonyl group, nonyloxycarbonyl group,decyloxycarbonyl group, 3,7-dimethyloctyloxycarbonyl group,dodecyloxycarbonyl group, trifluoromethoxycarbonyl group,pentafluoroethoxycarbonyl group, perfluorobutoxycarbonyl group,perfluorohexyloxycarbonyl group, perfluorooctyloxycarbonyl group,phenoxycarbonyl group, naphthoxycarbonyl group and pyridyloxycarbonylgroup. Note that the alkyl group, aryl group, arylalkyl group ormonovalent heterocyclic group may have a substituent. Note that thenumber of carbon atoms of the substituted carboxyl group does notinclude the number of carbon atoms of the substituent.

The divalent aromatic amine group refers to an atom group obtained byremoving two hydrogen atoms from an aromatic amine compound. The groupmay have a substituent. A specific structure of the divalent aromaticamine group is represented by the structure of the following formula(1).

In the formula, Ar₁, Ar₂, Ar₃ and Ar₄ each independently represent anarylene group or a divalent heterocyclic group; Ar₅, Ar₆ and Ar₇ eachindependently represent an aryl group or a monovalent heterocyclicgroup; Ar₁, Ar₂, Ar₃, Ar₄, Ar₅, Ar₆, and Ar₇ may have a substituent; andx and y each independently represent 0 or a positive integer. The typeof the substituent is not particularly limited. In view of solubility,fluorescent properties, ease of synthesis and characteristics of theresultant device, preferable examples of the substituent include analkyl group, alkoxy group, alkylthio group, aryl group, aryloxy group,arylthio group, arylalkyl group, arylalkoxy group, arylalkylthio group,arylalkenyl group, arylalkynyl group, amino group, substituted aminogroup, silyl group, substituted silyl group, halogen atom, acyl group,acyloxy group, imine residue, amide group, acid imido group, monovalentheterocyclic group, carboxyl group, substituted carboxyl group, nitrogroup, and cyano group.

Examples of the divalent aromatic amine group include groups representedby the following formulas 133 to 140.

The Rs of the above formulas are the same as defined in the formulas 1to 132.

To increase solubility of a polymer compound in an organic solvent, thepolymer compound preferably includes one or more atoms other than ahydrogen atom, and symmetricalness in shape of a repeat unit including asubstituent is preferably low.

In the aforementioned formulas, when R is a substituent including alkyl,in order to increase solubility of a polymer compound in an organicsolvent, one or more cyclic or branched alkyls are preferably contained.Furthermore, in the aforementioned formulas, when R partly contains anaryl group or a heterocyclic group, these groups may have one or moresubstituents. Among the structures represented by the formulas 133 to140, the structures represented by the formulas 134 and 137 arepreferable in view of adjusting light emission wavelength.

The repeat unit represented by the above formula (1) preferably includesAr₁, Ar₂, Ar₃ and Ar₄ each independently representing an arylene group,and Ar₅, Ar₆ and Ar₇ each independently representing an aryl group inview of adjusting light emission wavelength, device characteristics, andso on.

It is preferred that Ar₁, Ar₂, and Ar₃ each independently represent anunsubstituted phenylene group, unsubstituted biphenyl group,unsubstituted naphthylene group, or unsubstituted anthracene-diyl group.

In view of solubility in organic solvents, device characteristics, andso on, it is preferred that Ar₅, Ar₆ and Ar₇ each independentlyrepresent an aryl group including three or more substituents. Morepreferably, Ar₅, Ar₆ and Ar₇ represent a phenyl group including three ormore substituents; a naphthyl group including three or moresubstituents; or an anthranyl group including three or moresubstituents. Still more preferably, Ar₅, Ar₆ and Ar₇ represent a phenylgroup including three or more substituents.

Of them, it is preferable that Ar₅, Ar₆ and Ar₇ each independentlyrepresent the following formula (9) and satisfy the relationship: x+y≦3,more preferably x+y=1, and still more preferably x=1 and y=0.

In the formula, Re, Rf and Rg each independently represent an alkylgroup, alkoxy group, alkylthio group, aryl group, aryloxy group,arylthio group, arylalkyl group, arylalkoxy group, arylalkylthio group,arylalkenyl group, arylalkynyl group, amino group, substituted aminogroup, silyl group, substituted silyl group, silyloxy group, substitutedsilyloxy group, monovalent heterocyclic group, or halogen atom. Hydrogenatoms included in Re, Rf and Rg may be optionally substituted withfluorine atoms.

More preferably, in the formula (9), Re and Rf each independentlyrepresent an alkyl group having 3 or less carbon atoms, alkoxy grouphaving 3 or less carbon atoms or alkylthio group having 3 or less carbonatoms; and Rg is an alkyl group having 3 to 20 carbon atoms, alkoxygroup having 3 to 20 carbon atoms, or alkylthio group having 3 to 20carbon atoms.

In the repeat unit represented by the formula (9), Ar_(e) preferablyrepresent a group represented by the following formula (9-1) or (9-2).

In the formulas, the benzene ring(s) included in the structuresrepresented by (9-1) or (9-2) may each independently include a single ormore and four or less substituents; The substituents may be the same ordifferent; A plurality of the substituents may be linked to form a ring;and the benzene ring(s) may be linked to another aromatic hydrocarbonring or a heterocyclic ring.

Among the repeat units represented by the formula (1), specific examplesparticularly preferred are represented by the following formulas 141 and142.

Preferred polymers for forming light-emitting layers of polymer LEDsinclude any one of repeat units represented by the formula (1) and thefollowing formulas (2) to (8) in view of device characteristics, ease ofsynthesis, fluorescence intensity, and so on.

In the formula, ring A and ring B each independently represent anaromatic hydrocarbon ring that may have a substituent; two bonds arerespectively present on the ring A and/or the ring B; and R₁ and R₂ eachindependently represent a substituent.

In the formula, ring A and ring B represent the same as those mentionedabove; two bonds are respectively present on the ring A and/or the ringB; Z represents —O—, —S—, —S(═O)—, —S(═O)(═O)—, —N(R₃)—, —Si(R₃)(R₄)—,—P(═O)(R₃)—, —P(R₃)—, —B(R₃)—, —C(R₃)(R₄)—O—, —C(R₃)═N— or —Se—; and R₃and R₄ each independently represent a substituent.

In the formula, R₅ represents a substituent; n represents an integer of0 to 4; and when a plurality of R₅ are present, they may be the same ordifferent.

In the formula, R₆ and R₇ represent a substituent; o and p eachindependently represent an integer of 0 to 3; and when a plurality of R₆and R₇ are present, they may be the same or different.

In the formula, R₈, R₉, R₁₀, and R_(H) represent a substituent; q and reach independently represent an integer of 0 to 4; and when a pluralityof R₈ and R₉ are present, they may be the same or different.

In the formula, R₁₂ represents a substituent; u represents an integer of0 to 2; Ar₈ and Ar₉ each independently represent an arylene group,divalent heterocyclic group, or divalent group including a metal complexstructure; s and t each independently represent 0 or 1; X₁ represents—O—, —S—, —S(═O)—, —SO₂—, —Se—, or —Te—; and when a plurality of R₁₂ arepresent, they may be the same or different.

In the formula, Ar₁₀ and Ar₁₁ each independently represent an arylenegroup, divalent heterocyclic group, or divalent group including a metalcomplex structure; v and w each independently represent 0 or 1; X₂represents —O—, —S—, —S(═O)—, —S(═O)(═O)—, —Se—, —Te—, —NR₁₄—, or—SiR₁₅R₁₆—.

Specific structures of the formula (2) may include structuresrepresented by the following formulas 2-1 to 2-17.

In the formulas, R₁ and R₂ represent a substituent, and preferably ahydrogen atom, an alkyl group, alkoxy group, alkylthio group, arylgroup, aryloxy group, arylthio group, arylalkyl group, arylalkoxy group,arylalkylthio group, arylalkenyl group, arylalkynyl group, amino group,substituted amino group, silyl group, substituted silyl group, halogenatom, acyl group, acyloxy group, imine residue, amide group, acid imidogroup, monovalent heterocyclic group, carboxyl group, substitutedcarboxyl group, nitro group, or cyano group in view of solubility andease of synthesis. Examples of these groups are the same as thosementioned above. Among these substituents, preferred are an alkyl group,alkoxy group, aryl group, and aryloxy group. R₁ and R₂ may be linked toeach other to form a ring.

Examples of the formula (3) may include structures represented by thefollowing formulas 3-1 to 3-12.

Examples of the Rs in the formulas are the same as the Rs mentionedabove, and preferred Rs are an alkyl group, alkoxy group, aryl group,and aryloxy group. A plurality of hydrogen atoms in the formulas may besubstituted with the substituents R. R₃ and R₄ represent a substituent,and preferably a hydrogen atom, an alkyl group, alkoxy group, alkylthiogroup, aryl group, aryloxy group, arylthio group, arylalkyl group,arylalkoxy group, arylalkylthio group, arylalkenyl group, arylalkynylgroup, amino group, substituted amino group, silyl group, substitutedsilyl group, halogen atom, acyl group, acyloxy group, imine residue,amide group, acid imido group, monovalent heterocyclic group, carboxylgroup, substituted carboxyl group, nitro group, or cyano group in viewof solubility, ease of synthesis, and so on. Examples of these groupsare the same as those mentioned above. Among these substituents,preferred are an alkyl group, alkoxy group, aryl group, and aryloxygroup. In view of solubility, the structures preferably include one tothree alkyl groups, alkoxy groups, aryl groups, or aryloxy groups.

Examples of R₅, R₆, R₇, R₈, R₉, R₁₂, R₁₃, R₁₄, R₁₅, and R₁₆ in theformulas (4) to (8) include a hydrogen atom, an alkyl group, alkoxygroup, alkylthio group, aryl group, aryloxy group, arylthio group,arylalkyl group, arylalkoxy group, arylalkylthio group, arylalkenylgroup, arylalkynyl group, amino group, substituted amino group, silylgroup, substituted silyl group, halogen atom, acyl group, acyloxy group,imine residue, amide group, acid imido group, monovalent heterocyclicgroup, carboxyl group, substituted carboxyl group, nitro group, andcyano group. Examples of these groups are the same as those mentionedabove. Among these substituents, preferred are an alkyl group, alkoxygroup, aryl group, and aryloxy group. Examples of R₁₀ and R₁₁ in theformula (6) include a hydrogen atom, an alkyl group, alkoxy group,alkylthio group, aryl group, aryloxy group, arylthio group, arylalkylgroup, arylalkoxy group, arylalkylthio group, arylalkenyl group,arylalkynyl group, amino group, substituted amino group, silyl group,substituted silyl group, halogen atom, acyl group, acyloxy group, imineresidue, amide group, acid imido group, monovalent heterocyclic group,carboxyl group, substituted carboxyl group, nitro group, and cyanogroup. Examples of these groups are the same as those mentioned above.Among these substituents, preferred are a hydrogen atom, an alkyl group,and aryl group.

Examples of the formula (7) may include the following structures.

Examples of the Rs in the formulas are the same as the Rs mentionedabove, and preferred Rs are an alkyl group, alkoxy group, aryl group,and aryloxy group.

Preferred examples of the formula (8) include the following structures.

Examples of the Rs in the formulas are the same as the Rs mentionedabove, and preferred Rs are an alkyl group, alkoxy group, aryl group,and aryloxy group.

When the hole transport layer of a polymer LED is formed by using acomposition according to the present invention, preferred polymerscontained in the composition include polyvinylcarbazole or a derivativethereof; polysilane or a derivative thereof; polysiloxane derivativehaving an aromatic amine in a side chain or the main chain; pyrazolinederivative; arylamine derivative; stilbene derivative; triphenyl-diaminederivative; polyaniline or a derivative thereof; polythiophene or aderivative thereof; polypyrrole or a derivative thereof;poly(p-phenylenevinylene) or a derivative thereof;poly(2,5-thienylenevinylene) or a derivative thereof; and the polymersmentioned as examples used for forming a light-emitting layer.

When the electron transport layer of a polymer LED is formed by using acomposition according to the present invention, preferred polymerscontained in the composition include polyquinoline, polyquinoxaline, andother polymers mentioned as examples used for forming a light-emittinglayer.

Polymers contained in a composition according to the present inventioncan be produced by effecting reaction among monomers represented bygeneral formulas (10) and (11), and general formulas (12) and/or (13).

K₁—Ar₁₂—K₂  (10)

K₃—Ar₁₃—K₄  (11)

K₅-L₁  (12)

K₆-L₂  (13)

In the formulas, Ar₁₂ and Ar₁₃ each independently represent an arylenegroup, divalent heterocyclic group, divalent group including a metalcomplex structure, or a divalent aromatic amine group; L₁ and L₂independently represent an end group; K₁, K₂, K₃, K₄, K₅, and K₆ eachindependently represent a leaving group; and note that L₁ and L₂ aredifferent from each other.

Examples of the leaving group may include a halogen atom, analkylsulfonyloxy group, arylsulfonyloxy group, and —B(OR₁₇)₂ where R₁₁represents a hydrogen atom or an alkyl group.

Examples of the halogen atom may include a chlorine atom, bromine atomand iodine atom; preferably a chlorine atom and bromine atom; and themost preferably a bromine atom. The alkylsulfonyloxy group may beoptionally substituted with a fluorine atom, and examples of the groupmay include a trifluoromethanesulfonyloxy group. The arylsulfonyloxygroup may be optionally substituted with an alkyl group, and examples ofthe group may include a phenylsulfonyloxy group and trisulfonyloxygroup.

In the group represented by —B(OR₁₇)₂, R₁₇ represents a hydrogen atom oran alkyl group. The alkyl group generally has about 1 to 20 carbonatoms. Examples of the alkyl group may include a methyl group, ethylgroup, propyl group, butyl group, hexyl group, octyl group, and dodecylgroup. The alkyl groups may be linked to each other to form a ring.

Specific examples of the group represented by —B(OR₁₇)₂ are shown below.

Of them, preferred examples are shown below.

The total of charged amounts of the monomers of the general formulas(12) and (13) to that of the monomers of the general formulas (10) and(11) is generally 0.1 to 10 mole %, preferably 0.2 to 5 mole %, and morepreferably 0.5 to 3 mole %.

Examples of a method for producing the polymers according to the presentinvention may include: a method of polymerizing appropriate monomersmentioned above by Suzuki reaction (Chem. Rev., vol. 95, p. 2457(1995)); a polymerization method by Grignard reaction (PolymerFunctional Material Series vol. 2, Synthesis and Reaction of Polymers(2), p. 432-3, published by Kyoritsu Shuppan Co., Ltd.); apolymerization method by Yamamoto polymerization method (Prog. Polym.Sci., vol. 17, p. 1153-1205, 1992); a polymerization method using anoxidization agent such as FeCl₃; and an electrochemical oxidizationpolymerization method (The Fourth Series of Experimental Chemistry, vol.28, p. 339-340, published by Maruzen Co., Ltd.).

Herein, a case of employing the Suzuki reaction is described. In thiscase, for example, such monomers are used in which K₁ and K₂ eachindependently represent —B(OR₁₇)₂ where R₁₁ represents a hydrogen atomor an alkyl group; K₃ and K₄ each independently represent a halogenatom, an alkylsulfonyloxy group, or arylsulfonyloxy group; K₅ represents—B(OR₁₇)₂ where R₁₇ represents a hydrogen atom or an alkyl group; and K₆represents a halogen atom, an alkylsulfonyloxy group, or arylsulfonyloxygroup. A reaction among these monomers are effected in the presence of aPd(0) catalyst to produce the polymers.

In the above case, in a reaction in which at least one type of the twoor more types of monomers including two leaving groups to be used in thereaction is a monomer including two —B(OR₁₇)₂ where R₁₇ represents ahydrogen atom or an alkyl group; and at least one type of the two ormore types of monomers is a monomer including two halogen atoms,alkylsulfonyloxy groups, or arylsulfonyloxy groups, reaction proceduresare generally conducted by effecting reaction among monomers representedby the formulas (10) and (11) for about 1 to 100 hours, adding themonomer (12) to the system and effecting reaction for about 0.5 to 50hours, then adding the monomer (13) to the system and effecting reactionfor about 0.5 to 50 hours.

As the Pd(0) catalyst, for example,palladium[tetrakis(triphenylphosphine)], palladium acetates, or the likeis used. One or more equivalents, preferably 1 to 10 equivalents, of aninorganic base such as potassium carbonate, sodium carbonate, or bariumhydroxide; an organic base such as triethylamine; and an inorganic saltsuch as cesium fluoride are added to the monomers to effect reaction.The reaction may be effected by using an aqueous solution of theinorganic salt in two-phase system. Examples of a solvent may includeN,N-dimethylformamide, toluene, dimethoxy-ethane, or tetrahydrofuran.Depending on the solvent, reaction temperature is preferably about 50 to160° C. The system may be heated to about the boiling point of thesolvent, and then refluxed. Reaction time is about 1 to 200 hours.

A case of employing the Yamamoto polymerization method is described. Inthis case, for example, such monomers are used in which K₁, K₂, K₃, K₄,K₅ and K₆ each independently represent a halogen atom, analkylsulfonyloxy group, or arylsulfonyloxy group. A reaction among thesemonomers are effected in the presence of a Ni(0) complex to produce thepolymers. In general, the reaction is effected by mixing all themonomers (10) to (13).

As a method of using the Ni(0) complex (zerovalent nickel complex),there is a method of using zerovalent nickel itself and a method ofeffecting reaction of a nickel salt in the presence of a reducing agentto produce zerovalent nickel and using the zerovalent nickel in areaction. Examples of the zerovalent nickel complex may includebis(1,5-cyclooctadiene)nickel(0),(ethylene)bis(triphenylphosphine)nickel(0), andtetrakis(triphenylphosphine)nickel. Among these,bis(1,5-cyclooctadiene)nickel(0) is preferable in view of being suitablefor a wide variety of uses and inexpensive. Addition of a neutral ligandis preferable in view of increasing yield. The neutral ligand refers toa ligand without having an anion or a cation. Examples of the neutralligand may include a nitrogen-containing ligand such as 2,2′-bipyridyl,1,10-phenanthroline, methylenebisoxazoline, orN,N′-tetramethylethylenediamine; and a tertiary phosphine ligand such astriphenylphosphine, tritolylphosphine, tributylphosphine, ortriphenoxyphosphine. The nitrogen-containing ligand is preferable inview of being suitable for a wide variety of uses and inexpensive, and2,2′-bipyridyl is particularly preferable in view of high reactivity andhigh yield. In particular, a system containingbis(1,5-cyclooctadiene)nickel(0) to which 2,2′-bipyridyl is added as aneutral ligand is preferable in view of increasing the yield of thepolymers. In the method of using a zerovalent nickel in a reaction in asystem, examples of the nickel salt may include nickel chloride ornickel acetate. Examples of the reducing agent may include zinc, sodiumhydroxide, hydrazine and its derivatives, and lithium aluminum hydride.An additive such as ammonium iodide, lithium iodide, or potassium iodidemay be used as necessary. A polymerization solvent is not particularlyrestricted as long as the solvent does not inhibit polymerization, butthe solvent preferably contains one or more types of aromatichydrocarbon solvents and/or ether solvents. Herein, examples of thearomatic hydrocarbon solvents may include benzene, toluene, xylene,trimethylbenzene, tetramethylbenzene, butylbenzene, naphthalin, andtetralin; and toluene, xylene, tetralin, and tetramethylbenzene arepreferable. Examples of the ether solvent may include diisopropyl ether,tetrahydrofuran, 1,4-dioxane, diphenyl ether, ethylene glycol dimethylether, and tert-butylmethylether; and tetrahydrofuran and 1,4-dioxane,which are good solvents for polymers, are preferable. Among thesolvents, tetrahydrofuran is the most preferable. In view of improvingpolymerizability and solubility, a mixed solvent of the aromatichydrocarbon solvents and/or ether solvents and a solvent other thanaromatic hydrocarbon solvents and ether solvents may be used as long asthe mixed solvent does not inhibit polymerization reaction.

Reaction procedures and so on can be conducted, for example, accordingto a method shown in JP-A-2000-44544. In the Yamamoto polymerizationmethod, for example, a polymerization reaction is generally conductedunder an inert gas atmosphere such as argon or nitrogen in a solvent oftetrahydrofuran at a temperature of 60° C. in the presence of azerovalent nickel complex and a neutral ligand. Polymerization time isgenerally about 0.5 to 100 hours, but 10 hours or less is preferable inview of production cost. Polymerization temperature is generally about 0to 200° C., but 20 to 100° C. is preferable in view of high yield andlow cost for heating.

In the case of using a neutral ligand, the amounts of the neutral ligandto be used is preferably about 0.5 to 10 moles per 1 mole of azerovalent nickel complex in view of reaction yield and cost, morepreferably about 0.8 to 1.5 moles, and more preferably 0.9 to 1.1 moles.

The amounts of the zerovalent nickel complex to be used are notparticularly restricted as long as the complex does not inhibitpolymerization reaction. However, when the amounts of the complex aretoo small, the resulting polymer tends to have low molecular weight.When the amounts of the complex are too large, post handling tends to beburdensome. The amounts of the complex is preferably 0.1 to 10 moles to1 mole of a monomer, more preferably 1 to 5 moles, and still morepreferably 2 to 3.5 moles.

When a polymer is used as a light-emitting material for polymer LEDs,monomers before being polymerized are preferably purified by methodssuch as distillation, sublimation purification, or recrystallization,and then the monomers are polymerized. After the polymer is synthesized,a purification treatment such as fractionation like reprecipitationpurification or chromatography may be conducted.

The polymer contained in a composition according to the presentinvention may be one type, or two or more types. When the compositioncontains two or more types of polymers, the composition may contain apolymer that does not transport charges or a polymer that does not emitlight.

As for storage stability of a composition according to the presentinvention, it is preferred that viscosity change after a lapse of 30days since preparation of the composition is within ±5% of the viscosityon preparation, and more preferably viscosity change after a lapse of 90days since preparation of the composition is within ±5% of the viscosityon preparation.

Examples of the method of forming a thin film with a compositionaccording to the present invention include film forming methods such asspin-coating method, casting method, microgravure coating method,gravure-coating method, bar-coating method, roll-coating method,wire-bar coating method, dip-coating method, spray-coating method,screen printing method, flexographic printing method, offset printingmethod, and inkjet method. Among the methods, the composition accordingto the present invention is particularly suitable for forming films withthe inkjet method.

The inkjet method is conducted by dissolving a polymer in a solvent anddispensing the polymer with inkjet equipment or the like. The solutionmay contain an additive or a dopant on preparation of the solution. Theinkjet method is advantageous in that different colors can be appliedseparately and materials can be utilized efficiently with small loss ofthe materials.

The optimal value of thin film thickness differs depending upon amaterial to be used and uses. The film thickness is, for example, 1 nmto 1 μm, preferably 2 nm to 500 nm, and further preferably, 5 nm to 200nm.

A composition according to the present invention is characterized inthat a thin film with uniform thickness is formed with the composition.A thin film with uniform thickness causes less light-emissionirregularity when the film is used as the light-emitting layer of apolymer LED, and a device with such a polymer LED has a longer luminancehalf life period. Herein, a uniform film preferably refers to a filmhaving a planar profile particularly in the central portion of the film.A film with slightly convex or concave profile does not cause problemsbecause light-emission irregularity is small. However, a thin film witha greatly concave profile causes considerable light-emissionirregularity, and a device with such a film has a shorter luminance halflife period. There are various methods for measuring profiles of thinfilms. For example, there is a method of charging a liquefiedcomposition into a syringe, dispensing the composition on a glasssubstrate with the syringe to which a high precision needle is attached,drying the composition, and then measuring the profile of the dried thinfilm with an interference microscope. The thin film may be dried at roomtemperature or at an elevated temperature, under a normal pressure or areduced pressure.

The profile of a thin film can be evaluated visually by looking at theprofile, but can also be evaluated based on the film thickness of thecentral portion of the film and the film thickness of the thickestportion of the film. That is, in view of reducing light-emissionirregularity, a value obtained by dividing the film thickness of thethickest portion by the film thickness of the central portion of a filmis preferably equal to or less than 1.50, more preferably equal to orless than 1.35, still more preferably equal to or less than 1.20, yetmore preferably equal to or less than 1.10, and still yet morepreferably equal to or less than 1.05.

A polymer LED according to the present invention comprises alight-emitting layer between electrodes consisting of an anode and acathode and characterized in that the light-emitting layer is formedwith the composition according to the present invention. The polymer LEDaccording to the present invention includes a polymer light-emittingdevice at least comprising a layer containing a conductive polymeradjacent to one of the electrodes between the electrode and thelight-emitting layer; and a polymer light-emitting device at leastcomprising a insulation layer with an average film thickness of 2 nm orless adjacent to one of the electrodes between the electrode and thelight-emitting layer.

Furthermore, examples of a polymer LED according to the presentinvention include

a polymer LED formed by providing an electron transport layer between ancathode and a light-emitting layer;

a polymer LED formed by providing a hole transport layer between ananode and a light-emitting layer; and

a polymer LED formed by providing an electron transport layer between ancathode and a light-emitting layer and a hole transport layer betweenthe anode and the light-emitting layer.

Specific examples of a structure of a polymer LED according to thepresent invention include the following structures a) to d).

a) anode/light-emitting layer/cathode

b) anode/hole transport layer/light-emitting layer/cathode

c) anode/light-emitting layer/electron transport layer/cathode

d) anode/hole transport layer/light-emitting layer/electron transportlayer/cathode

(where the mark “/” means that individual layers are stacked in adjacentto each other.)

Herein, the light-emitting layer is a layer with a function to emitlight; the hole transport layer is a layer with a function to transportholes; and an electron transport layer is a layer with a function totransport electrons. Note that the electron transport layer and the holetransport layer are collectively called as a charge transport layer. Thelight-emitting layer, the hole transport layer, and the electrontransport layer may be independently used as two or more layers.

Of the charge transport layers provided in adjacent to an electrode, onehaving a function of improving charge injection efficiency from theelectrode and an effect of reducing the driving voltage of the device isgenerally called particularly as a charge injection layer (holeinjection layer, electron injection layer) in some cases.

To improve adhesion properties to an electrode and improve chargeinjection from the electrode, the charge injection layer or aninsulating layer of 2 nm or less in thickness may be provided inadjacent to the electrode. Alternatively, to improve adhesion propertiesto the interface or to prevent contamination, a thin insulating layermay be inserted into the interface between a charge transport layer anda light-emitting layer. The order, number and thickness of layers to bestacked can be appropriately set in consideration of light emissionefficiency and the lifespan of a device.

In the present invention, as a polymer LED having a charge injectionlayer (electron injection layer, hole injection layer) provided therein,mention may be made of a polymer LED having a charge injection layer inadjacent to a cathode and a polymer LED having an charge injection layerin adjacent to an anode. For example, the following structures e) to p)may be specifically mentioned.

e) anode/charge injection layer/light-emitting layer/cathodef) anode/light-emitting layer/charge injection layer/cathodeg) anode/charge injection layer/light-emitting layer/charge injectionlayer/cathodeh) anode/charge injection layer/hole transport layer/light-emittinglayer/cathodei) anode/hole transport layer/light-emitting layer/charge injectionlayer/cathodej) anode/charge injection layer/hole transport layer/light-emittinglayer/charge injection layer/cathodek) anode/charge injection layer/light-emitting layer/electron transportlayer/cathodel) anode/light-emitting layer/electron transport layer/charge injectionlayer/cathodem) anode/charge injection layer/light-emitting layer/electron transportlayer/charge injection layer/cathoden) anode/charge injection layer/hole transport layer/light-emittinglayer/electron transport layer/cathodeo) anode/hole transport layer/light-emitting layer/electron transportlayer/charge injection layer/cathodep) anode/charge injection layer/hole transport layer/light-emittinglayer/electron transport layer/charge injection layer/cathode.

Specific examples of the charge injection layer include

a layer containing an electric conductive polymer;

a layer formed between an anode and a hole transport layer andcontaining ionization potential value between that of an anode materialand a hole transportable material contained in the hole transport layer;and

a layer provided between a cathode and an electron transport layer andhaving an electron affinity value between that of an anode material andan electron transportable material contained in the electron transportlayer.

When the charge injection layer is a layer containing an electricconductive polymer, the electric conductivity of the electric conductivepolymer is preferably 10⁻⁵ S/cm to 10³ (both inclusive), more preferably10⁻⁵ S/cm to 10² (both inclusive), and further preferably 10⁻⁵ S/cm to10¹ (both inclusive) to reduce a leakage current between light-emittingpixels.

When the charge injection layer is a layer containing an electricconductive polymer, the electric conductivity of the electric conductivepolymer is preferably 10⁻⁵ S/cm to 10³ S/cm (both inclusive), morepreferably 10⁻⁵ S/cm to 10² S/cm (both inclusive), and furtherpreferably 10⁻⁵ S/cm to 10¹ S/cm (both inclusive) to reduce a leakagecurrent between light-emitting pixels. To set an electric conductivityof the electric conductive polymer at 10⁻⁵ S/cm to 10³ (both inclusive),generally an appropriate amount of ions are doped in the electricconductive polymer.

The type of ions, if they are doped into a hole injection layer, areanion and if they are doped into an electron injection layer, arecations. Examples of the anions include polystyrene sulfonic acid ion,alkylbenzene sulfonic acid ion and camphor sulfonic acid ion. Examplesof the cations include lithium ion, sodium ion, potassium ion andtetrabutylammonium ion. The film thickness of a charge injection layeris from 1 nm to 100 nm, and preferably, 2 nm to 50 nm.

The material to be used in a charge injection layer may be appropriatelyselected in connection with the material to be used in a layer adjacentto an electrode. Examples thereof include polyaniline or a derivativethereof;

polythiophene or a derivative thereof;

polypyrrole or a derivative thereof;

polyphenylenevinylene or a derivative thereof;

polythienylenevinylene or a derivative thereof;

polyquinoline or a derivative thereof;

polyquinoxaline or a derivative thereof;

an electric conductive polymer such as a polymer containing an aromaticamine structure in the main chain or a side chain;

metal phthalocyanine (such as copper phthalocyanine); and

carbon.

The insulating layer having a film thickness of 2 nm or less has afunction of facilitating charge injection. Examples of the material ofthe insulating layer include a metal fluoride, metal oxide and organicinsulating material. Examples of a polymer LED having an insulatinglayer of a film thickness of 2 nm or less include

a polymer LED having an insulating layer having a film thickness of 2 nmor less in adjacent to a cathode, and

a polymer LED having an insulating layer having a film thickness of 2 nmor less in adjacent to an anode.

For example, the following structures q) to ab) may be specificallymentioned.

q) anode/insulating layer having a film thickness of 2 nm orless/light-emitting layer/cathoder) anode/light-emitting layer/insulating layer having a film thicknessof 2 nm or less/cathodes) anode/insulating layer having a film thickness of 2 nm orless/light-emitting layer/insulating layer having a film thickness of 2nm or less/cathodet) anode/insulating layer having a film thickness of 2 nm or less/holetransport layer/light-emitting layer/cathodeu) anode/hole transport layer/light-emitting layer/insulating layerhaving a film thickness of 2 nm or less/cathodev) anode/insulating layer having a film thickness of 2 nm or less/holetransport layer/light-emitting layer/insulating layer having a filmthickness of 2 nm or less/cathodew) anode/insulating layer having a film thickness of 2 nm orless/light-emitting layer/electron transport layer/cathodex) anode/light-emitting layer/electron transport layer/insulating layerhaving a film thickness of 2 nm or less/cathodey) anode/insulating layer having a film thickness of 2 nm orless/light-emitting layer/electron transport layer/insulating layerhaving a film thickness of 2 nm or less/cathodez) anode/insulating layer having a film thickness of 2 nm or less/holetransport layer/light-emitting layer/electron transport layer/cathodeaa) anode/hole transport layer/light-emitting layer/electron transportlayer/insulating layer having a film thickness of 2 nm or less/cathodeab) anode/insulating layer having a film thickness of 2 nm or less/holetransport layer/light-emitting layer/electron transport layer/insulatinglayer having a film thickness of 2 nm or less/cathode

The optimal value of film thickness of the light-emitting layer differsdepending upon a material to be used. The film thickness may be selectedsuch that driving voltage and light emission efficiency takeappropriately values. The film thickness is, for example, 1 nm to 1 μm,preferably 2 nm to 500 nm, and further preferably, 5 nm to 200 nm.

The light-emitting layer can also be formed with a composition accordingto the present invention.

When a polymer LED according to the present invention has a holetransport layer, examples of the hole transportable material to beemployed include polyvinylcarbazole or a derivative thereof; polysilaneor a derivative thereof; polysiloxane derivative having an aromaticamine in a side chain or the main chain; pyrazoline derivative;arylamine derivative; stilbene derivative; triphenyl-diamine derivative;polyaniline or a derivative thereof; polythiophene or a derivativethereof; polypyrrole or a derivative thereof; poly(p-phenylenevinylene)or a derivative thereof; and poly(2,5-thienylenevinylene) or aderivative thereof.

Specific examples of the hole transportable material include thosedescribed in JP-A-63-70257, JP-A-63-175860, JP-A-2-135359,JP-A-2-135361, JP-A-2-209988, JP-A-3-37992, and JP-A-3-152184.

Of them, as a hole transportable material for use in hole transportlayer, mention may be preferably made of polymer hole transportablematerials such as polyvinylcarbazole or a derivative thereof, polysilaneor a derivative thereof, a polysiloxane derivative having an aromaticamine compound group in a side chain or the main chain, polyaniline or aderivative thereof, polythiophene or a derivative thereof,poly(p-phenylenevinylene) or a derivative thereof, andpoly(2,5-thienylenevinylene) or a derivative thereof; and morepreferably, polyvinylcarbazole or a derivative thereof, polysilane or aderivative thereof, a polysiloxane derivative having an aromatic aminein a side chain or the main chain. The hole transportable material of alow molecular compound is preferably used by dispersing it in a polymerbinder.

Poly(N-vinylcarbazole) or a derivative thereof can be obtained from avinyl monomer through cation polymerization or radical polymerization.

Examples of polysilane or a derivative thereof include compoundsdescribed in Chem. Rev. Vol. No. 89, p. 1359 (1989) and the publishedspecification of British Patent GB2300196. As a synthetic methodthereof, the method described in these documents can be used. Inparticular, the Kipping method can be suitably used.

In polysiloxane or a derivative thereof, since a polysiloxane skeletonstructure has no hole transportability, one having the aforementionedstructure of a low molecular weight hole transportable material in aside chain or the main chain is suitably used. In particular, one havinga hole transportable aromatic amine in a side chain or the main chainmay be mentioned.

A method of forming a hole transfer layer film is not particularlylimited. In the case of low molecular weight hole transportablematerial, a method of forming a film from a mixed solution with apolymer binder may be mentioned. In the case of a high molecular weighthole transportable material, a method of forming a film from a solutionmay be mentioned.

A solvent for use in film-formation from a solution is not particularlyrestricted as long as the solvent dissolves a hole transportablematerial. Examples of the solvent may include the solvents used for thesolution composition according to the present invention.

Examples of the film formation method from a solution include aspin-coating method, casting method, microgravure coating method,gravure-coating method, bar-coating method, roll-coating method,wire-bar coating method, dip-coating method, spray-coating method,screen printing method, flexographic printing method, offset printingmethod and inkjet method.

As the polymer binder to be mixed, it is preferred to use one which doesnot inhibit charge transfer extremely. Furthermore, it is suitable touse one having no intensive absorption to visible light. Example of thepolymer binder include polycarbonate, polyacrylate, polymethylacrylate,polymethylmethacrylate, polystyrene, polyvinylchloride and polysiloxane.

As the film thickness of a hole transport layer, its optimal valuevaries depending upon the material to be used. The film thickness may beselected such that driving voltage and light emission efficiency takeappropriately values. However, it is at least required to have asufficient film thickness not to produce pin holes. The extremely thickfilm is not preferable because the driving voltage of the deviceincreases. Accordingly, the film thickness of the hole transport layeris, for example, from 1 nm to 1 μm, preferably 2 nm to 500 nm, andfurther preferably, 5 nm to 200 nm.

The hole transport layer can also be formed with a composition accordingto the present invention.

When a polymer LED according to the present invention has an electrontransport layer, as the electron transportable material to be used, aknown material may be used. Examples thereof include

a metal complex of oxadiazole derivative thereof;

anthraquinodimethane derivative thereof,

benzoquinone or a derivative thereof,

naphthoquinone or a derivative thereof,

anthraquinone or a derivative thereof,

tetracyanoanthraquino-dimethane or a derivative thereof,

fluorenone derivative,

diphenyl-dicyanoethylene or a derivative thereof;

diphenoquinone derivative, or

8-hydroxyquinoline or a derivative thereof;

polyquinoline or a derivative thereof;

polyquinoxaline or a derivative thereof; and

polyfluorene or a derivative thereof.

Specific examples include those described in JP-A-63-70257,JP-A-63-175860, JP-A-2-135359, JP-A-2-135361, JP-A-2-209988,JP-A-3-37992 and JP-A-3-152184.

Of them, mention is preferably made of a metal complex of oxadiazolederivative thereof,

benzoquinone or a derivative thereof,

anthraquinone or a derivative thereof, or

8-hydroxyquinoline or a derivative thereof;

polyquinoline or a derivative thereof;

polyquinoxaline or a derivative thereof; and

polyfluorene or a derivative thereof, and further preferably,

2-(4-viphenyl)-5-(4-t-butylphenyl)-1,3,4-oxadiazole, benzoquinone,anthraquinone, tris(8-quinolyl)aluminum and polyquinoline.

A film formation method for an electron transport layer is notparticularly limited. Examples of a film formation method using a lowmolecular weight electron transportable material include a vacuumdeposition method for forming a film from powder and a method forforming a film from a solution or molten state. Examples of a filmformation method using a high molecular weight electron transportablematerial include a method of forming a film from a solution or moltenstate. In the method of forming a film from a solution or molten state,a polymer binder may be used together.

A solvent for use in film-formation from a solution is not particularlyrestricted as long as the solvent dissolves an electron transportablematerial and/or a polymer binder. Examples of the solvent include

chlorine base solvents such as chloroform, methylene chloride, anddichloroethane;

ether base solvents such as tetrahydrofuran;

aromatic hydrocarbon base solvents such as toluene and xylene;

ketone base solvents such as acetone and methylethyl ketone; and

ester solvents such as ethyl acetate, butyl acetate and ethyl-cellosolveacetate.

As a method of forming a film from a solution or a molten state, use maybe made of coating methods such as a spin-coating method, castingmethod, microgravure coating method, gravure-coating method, bar-coatingmethod, roll-coating method, wire-bar coating method, dip-coatingmethod, spray-coating method, screen printing method, flexographicprinting method, offset printing method and inkjet method.

As the polymer binder to be mixed, it is preferred to use one which doesnot inhibit charge transfer extremely. Furthermore, it is suitable touse one having no intensive absorption to visible light. Example of thepolymer binder include poly(N-vinylcarbazole), polyaniline or aderivative thereof, polythiophene or a derivative thereof,poly(p-phenylenevinylene) or a derivative thereof,poly(2,5-thienylenevinylene) or a derivative thereof, polycarbonate,polyacrylate, polymethylacrylate, polymethylmethacrylate, polystyrene,polyvinylchloride and polysiloxane.

As the film thickness of an electron transport layer, its optimal valuevaries depending upon the material to be used. The film thickness may beselected such that driving voltage and light emission efficiency takeappropriately values. However, it is at least required to have asufficient film thickness not to produce pin holes. The extremely thickfilm is not preferable because the driving voltage of the deviceincreases. Accordingly, the film thickness of the electron transportlayer is, for example, from 1 nm to 1 μm, preferably 2 nm to 500 nm, andfurther preferably, 5 nm to 200 nm.

The electron transport layer can also be formed with a compositionaccording to the present invention.

As a substrate on which a polymer LED according to the present inventionis formed, any substrate may be used as long as it cannot be influencedwhen an electrode is formed and then an organic material layer isformed. Examples of the substrate include substrates formed of glass,plastic, polymer film and silicon. When an opaque substrate is used, theopposite electrode is preferably transparent or semitransparent.

Generally, at least one of the electrodes consisting of an anode and acathode is transparent or semitransparent. The anode is preferablytransparent or semitransparent. As the material for the anode, use maybe made of, for example, a conductive metal oxide film andsemitransparent metal thin film. Specific examples thereof include afilm (NESA) formed of electrically conductive glass made of, forexample, indium oxide, zinc oxide, tin oxide; and composites these suchas indium tin oxide (ITO), indium/zinc/oxide, gold, platinum, silver andcopper; and ITO, indium/zinc/oxide and tin oxide are preferable.Examples of the forming method include a vacuum deposition method,sputtering method, ion plating method and plating method. Furthermore,as the anode, use may be made of an organic electric conductive filmsuch as polyaniline or a derivative thereof or polythiophene or aderivative thereof. The film thickness of an anode may be appropriatelyset in consideration of light permeability and electric conductivity,and is for example, 10 nm to 10 μm, preferably, 20 nm to 1 μm, andfurther preferably, 50 nm to 500 nm. To facilitate injection of charge,a layer having an average thickness of 2 nm and formed of aphthalocyanine derivative, electric conductive polymer or carbon orformed of a metal oxide, metal fluoride or an organic insulatingmaterial, may be provided on the anode.

As a material for the cathode to be used in a polymer LED according tothe present invention, one having a small work function is preferable.Examples of the material to be used include

metals such as lithium, sodium, potassium, rubidium, cesium, beryllium,magnesium, calcium, strontium, barium, aluminum, scandium, vanadium,zinc, yttrium, indium, cerium, samarium, europium, terbium, andytterbium;

alloys formed of at least two of them;

alloys formed of at least one of them and one selected from the groupconsisting of gold, silver, platinum, copper, manganese, titanium,cobalt, nickel, tungsten and tin;

graphite; and a graphite intercalation compound.

Examples of the alloy include

Magnesium-silver alloy, magnesium-indium alloy, magnesium-aluminumalloy, indium-silver alloy, lithium-aluminum alloy, lithium-magnesiumalloy, lithium-indium alloy and calcium-aluminum alloy. The cathode mayhave a stacked structure consisting of two or more layers. The filmthickness of a cathode may be appropriately set in consideration ofelectric conductivity and durability, and is for example, 10 nm to 10μm, preferably 20 nm to 1 μm and further preferable 50 nm to 500 nm.

Examples of the method of forming a cathode include a vacuum depositionmethod, sputtering method, laminate method in which a metal thin film isformed by thermocompression bonding. Furthermore, a layer formed of anelectric conductive polymer or a layer formed of e.g., a metal oxide,metal fluoride, or organic insulating material and having an averagefilm thickness of 2 nm or less may be provided between the cathode andan organic layer. Alternatively, after the cathode is formed, aprotecting layer for protecting the polymer LED may be applied. To usethe polymer LED stably for a long time, the device may be externallyprotected preferably with a protecting layer and/or a protecting cover.

As the protecting layer, use may be made of e.g., a polymer compound,metal oxide, metal fluoride and metal borate. Furthermore, as theprotecting cover, use may be made of e.g., glass plate and plastic plateon the surface of which treatment of lowing water permeability isapplied. A method of adhering the cover tight with the substrate of adevice with a thermoplastic resin or a photosetting resin, therebysealing them, is preferably used. It is easy to prevent the device frombeing damaged by keeping a space by use of a spacer. If an inert gassuch as nitrogen or argon is introduced into the space, it is possibleto prevent oxidation of the cathode. Furthermore, if a desiccating agentsuch as barium oxide is placed in the space, it is possible to suppressa moisture content adsorbed in the manufacturing step from damaging thedevice. At least one of the methods is preferably employed.

A polymer light-emitting device according to the present invention maybe used as a planar light source or a backlight of a segment typedisplay device, a dot matrix display device, a liquid crystal displaydevice, and the like.

To obtain planar light emission by use of a polymer LED according to thepresent invention, a planar anode and a planar cathode are placed so asto overlap with each other. To obtain patterned light emission, thereare

a method in which a mask having a patterned window is provided on thesurface of the planar light-emitting device;

a method in which an organic material layer used in non light-emittingportion is formed extremely thick substantially not to emit light fromthe portion; and

a method in which either one of or both of the anode and cathode areformed so as to have a pattern. A pattern is formed in accordance withany one of the methods, and several electrodes are arranged so as toindependently turn ON/Off. In this way, it is possible to obtain asegment type display device capable of displaying numerical values,characters, and simple symbols. Furthermore, to obtain a dot-matrixdevice, both an anode and a cathode may be formed in stripe form andarranged so as to cross perpendicularly with each other. Sector colordisplay and multicolor display can be attained by a method of separatelyapplying a plurality of types of polymer phosphors different in emissioncolor, or by a method of using a color filter or a fluorescentconversion filter. A dot matrix device can be driven passively and maybe driven actively in combination with, for example, TFT. These displaydevices can be used as display devices of a computer, television,portable handheld unit, mobile phone, car navigation and a view finderof a video camera, etc.

Furthermore, the planar light-emitting device is a thin-film spontaneouslight-emitting device and suitably used as a planar light source for abacklight of a liquid crystal display device or a planar illuminationlight source. Furthermore, if a flexible substrate is used, the planarlight emitting device can be used also as a curved surface light sourceor display device.

Furthermore, the solution composition of the present invention may beused for preparing a laser dye layer, a material for an organic solarbattery, an organic semiconductor for an organic transistor and amaterial for a conductive thin film.

EXAMPLES

Now, the present invention will be more specifically explained withreference to Examples below, which will not be construed as limiting theinvention.

Herein, as to number average molecular weight and weight averagemolecular weight, gel permeation chromatography (GPC) (tradename:LC-10Avp manufactured by SHIMADZU CORPORATION) was used to determine Zaverage molecular weight, number average molecular weight, and weightaverage molecular weight relative to polystyrene. A polymer to bemeasured was dissolved in tetrahydrofuran so that its concentrationbecame about 0.5 wt %, and 50 μL of this solution was injected into theGPC. Tetrahydrofuran was used for mobile phase of the GPC and flowed ata rate of 0.6 mL/min. As for a column, two TSKgel SuperHM-H (tradename,manufactured by Tosoh Corporation) and one TSKgel SuperH2000 (tradename,manufactured by Tosoh Corporation) were combined serially. As for adetector, a differential refractometer detector (tradename: RID-10Amanufactured by SHIMADZU CORPORATION) was used.

The profile of a thin film was measured by charging 3 mL of acomposition into a syringe, dispensing the composition on a glasssubstrate with the syringe to which a high precision needle FN-002N(tradename, 20 μm pore size, manufactured by Musashi Engineering, Inc.)is attached, drying the composition under a reduced pressure in vacuo atan ordinary temperature for 10 minutes, and then measuring the profileof the dried thin film with an interference microscope Micromap557N(tradename, manufactured by Micromap Corporation). In measuringviscosity, LVDV-II+Pro (tradename) manufactured by BROOKFIELDEngineering Laboratories was used.

Synthesis Example 1 Synthesis of Polymer 1

Under a nitrogen atmosphere, 195.37 g of the following compound A,239.44 g of the following compound B, and 232.89 g of 2,2′-bipyridylwere dissolved in 46.26 kg of dehydrated tetrahydrofuran. After that,this solution was heated up to 60° C., 410.15 g ofbis(1,5-cyclooctadiene)nickel(0) {Ni(COD)₂} was added thereto, therebyeffecting a reaction for 5 hours. After the reaction was complete, thisreaction solution was cooled to room temperature, added dropwise to amixed solution of 8.52 kg of 25% aqueous ammonia/16.88 kg ofmethanol/31.98 kg of ion exchanged water, and stirred for 2 hours. Afterthat, precipitated substance was filtrated and dried under a reducedpressure. After the drying, the substance was dissolved in 16.22 kg oftoluene. After the dissolution, 830 g of Radiolight was added theretoand insoluble matters were filtrated. Thus obtained filtrate waspurified through an alumina column. Subsequently, the purified solutionwas added to a mixture of 13.52 kg of ion exchanged water/2.04 kg of 25%aqueous ammonia, stirred for 0.5 hours and the water layer was removed.Furthermore, 13.52 kg of ion exchanged water was added to the organiclayer, stirred for 0.5 hours and the water layer was removed. A part ofthe resulting organic layer was concentrated under a reduced pressureand added to 34.18 kg of methanol and stirred for an hour. The resultingprecipitated substance was filtrated and dried under a reduced pressure.The yield of the resulting polymer (hereafter, referred to as Polymer 1)was 234.54 g. The number average molecular weight of Polymer 1 relativeto polystyrene was Mn=1.2×10⁴. The weight average molecular weight ofPolymer 1 relative to polystyrene was Mw=7.7×10⁴.

Example 1 Production of Composition 1

0.10 g of Polymer 1 was dissolved in a mixed solution of 3.0 g ofphenetole and 7.0 g of acetophenone (boiling point: 202° C.) to produceComposition 1.

Production Example 1 Production of Composition 2

0.10 g of Polymer 1 was dissolved in a mixed solution of 3.0 g ofanisole and 7.0 g of xylene (boiling point: 137 to 140° C.) to produceComposition 2.

Measurement Example 1 Viscosity Measurement of Composition 2

The viscosity of Composition 2 was measured to be 1.1 mPa·s.

Example 2 Forming of Thin Film

A thin film was formed by the above-mentioned method with Composition 1.The profile of the thin film was close to a plane as shown in FIG. 1.The value obtained by dividing the film thickness of the thickestportion by the film thickness of the central portion of the film was1.15.

Comparative Example 1 Forming of Thin Film

A thin film was formed by the above-mentioned method with Composition 2.The profile of the thin film was concave as shown in FIG. 2. The valueobtained by dividing the film thickness of the thickest portion by thefilm thickness of the central portion of the film was 2.38.

Example 3 Production of Composition 3

0.10 g of Polymer 1 was dissolved in a mixed solution of 3.0 g ofphenetole and 7.0 g of bicyclohexyl (boiling point: 226 to 228° C.) toproduce Composition 3.

Example 4 Viscosity Measurement of Composition 3

The viscosity of Composition 3 was measured to be 3.0 mPa·s.

Example 5 Evaluation of Fluorescence Characteristics of Composition 3

Composition 3 was spin-coated on a quarts plate to form a polymer thinfilm. The fluorescence spectrum of the thin film was measured with afluorescence spectrophotometer (tradename: Fluorolog manufactured byJOBINYVON-SPEX) with an excitation wavelength of 350 nm.

The fluorescence peak wavelength of Composition 3 was 457 nm.

Example 6 Production of Composition 4

0.10 g of Polymer 1 was dissolved in a mixed solution of 3.0 g ofphenetole and 7.0 g of n-dodecane (boiling point: 216° C.) to produceComposition 4.

Example 7 Production of Composition 5

0.10 g of Polymer 1 was dissolved in a mixed solution of 5.0 g ofphenoxyphenol and 5.0 g of tetralin (boiling point: 207° C.) to produceComposition 5.

Example 8 Viscosity Measurement of Composition 5

The viscosity of Composition 5 was measured to be 4.1 mPa·s.

Example 9 Production of Composition 6

0.10 g of Polymer 1 was dissolved in a mixed solution of 7.0 g oftetralin (boiling point: 207° C.) and 3.0 g of bicyclohexyl (boilingpoint: 226 to 228° C.) to produce Composition 6.

Example 10 Forming of Thin Film

A thin film was formed by the above-mentioned method with Composition 6.The profile of the thin film was close to a plane as shown in FIG. 3.The value obtained by dividing the film thickness of the thickestportion by the film thickness of the central portion of the film was1.14.

Example 11 Viscosity Measurement of Composition 6

The viscosity of Composition 6 was measured to be 4.0 mPa·s.

Example 12 Production of Composition 7

0.10 g of Polymer 1 was dissolved in a mixed solution of 3.0 g oftetralin (boiling point: 207° C.) and 7.0 g of2-(1-cyclohexenyl)cyclohexanone (boiling point: 265° C.) to produceComposition 7.

Example 13 Viscosity Measurement of Composition 7

The viscosity of Composition 7 was measured to be 8.8 mPa·s.

Example 14 Production of Composition 8

0.10 g of Polymer 1 was dissolved in a mixed solution of 3.0 g of methylbenzoate (boiling point: 199° C.) and 7.0 g of bicyclohexyl (boilingpoint: 226 to 228° C.) to produce Composition 8.

Example 15 Viscosity Measurement of Composition 8

The viscosity of Composition 8 was measured to be 3.6 mPa·s.

Example 16 Evaluation of Fluorescence Characteristics of Composition 8

Composition 8 was spin-coated on a quarts plate to form a polymer thinfilm. The fluorescence spectrum of the thin film was measured with afluorescence spectrophotometer (tradename: Fluorolog manufactured byJOBINYVON-SPEX) with an excitation wavelength of 350 nm.

The fluorescence peak wavelength of Composition 8 was 464 nm.

1. A composition comprising two or more organic compounds having boilingpoints equal to or higher than 100° C. except for aromatic ethercompounds, and one or more polymers that transport charges or emit lightin a solid state, characterized in that at least one of the organiccompounds are selected from aliphatic compounds that may optionallyinclude a hetero atom and alicyclic compounds that may optionallyinclude a hetero atom, the aliphatic compounds and the alicycliccompounds having boiling points equal to or higher than 200° C.
 2. Thecomposition according to claim 1, wherein the organic compounds selectedfrom the aliphatic compounds and the alicyclic compounds having boilingpoints equal to or higher than 200° C. have melting points equal to orlower than 25° C.
 3. The composition according to claim 1, wherein thealicyclic compounds comprise a carbon 6-membered ring structure.
 4. Thecomposition according to claim 1, comprising the aliphatic compounds orthe alicyclic compounds having boiling points equal to or higher than200° C. in an amount equal to or greater than 30 wt % based on a totalweight of the composition.
 5. The composition according to claim 1,wherein the polymers have weight average molecular weights of 1.0×10³ to1.0×10⁷ relative to polystyrene.
 6. The composition according to claim1, comprising 0.1 to 5.0 wt % of the polymers based on a total weight ofthe composition.
 7. The composition according to claim 1, having aviscosity of 1 to 20 mPa·s.
 8. A thin film characterized by being formedwith the composition according to claim
 1. 9. The thin film according toclaim 8, wherein a value obtained by dividing a film thickness of athickest portion by a film thickness of a central portion of the film isequal to or less than 1.50.
 10. A polymer light-emitting devicecomprising at least a light-emitting layer between electrodes consistingof an anode and a cathode, characterized in that the light-emittinglayer is formed with the composition according to claim 1 comprising oneor more polymers that emit light in a solid state.
 11. A polymerlight-emitting device comprising at least a light-emitting layer and ahole transport layer between electrodes consisting of an anode and acathode, characterized in that the hole transport layer is formed withthe composition according to claim 1 comprising one or more polymersthat transport charges.
 12. A polymer light-emitting device comprisingat least a light-emitting layer and an electron transport layer betweenelectrodes consisting of an anode and a cathode, characterized in thatthe electron transport layer is formed with the composition according toclaim 1 comprising one or more polymers that transport charges.
 13. Amethod for forming the polymer light-emitting device according to claim10, characterized by using a print method.
 14. A method for forming thepolymer light-emitting device according to claim 10, characterized byusing an inkjet method.